diff --git a/SabreTools.Models/OfflineList/CanOpen.cs b/SabreTools.Models/OfflineList/CanOpen.cs
new file mode 100644
index 00000000..a39b819f
--- /dev/null
+++ b/SabreTools.Models/OfflineList/CanOpen.cs
@@ -0,0 +1,12 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("canOpen")]
+    public class CanOpen
+    {
+        [XmlElement("extension")]
+        public string[]? Extension { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/Configuration.cs b/SabreTools.Models/OfflineList/Configuration.cs
new file mode 100644
index 00000000..0ea8dc84
--- /dev/null
+++ b/SabreTools.Models/OfflineList/Configuration.cs
@@ -0,0 +1,41 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("configuration")]
+    public class Configuration
+    {
+        [XmlElement("datName")]
+        public string? DatName { get; set; }
+
+        [XmlElement("datVersion")]
+        public string? DatVersion { get; set; }
+
+        [XmlElement("system")]
+        public string? System { get; set; }
+
+        /// <remarks>Numeric?</remarks>
+        [XmlElement("screenshotsWidth")]
+        public string? ScreenshotsWidth { get; set; }
+
+        /// <remarks>Numeric?</remarks>
+        [XmlElement("screenshotsHeight")]
+        public string? ScreenshotsHeight { get; set; }
+
+        [XmlElement("infos")]
+        public Infos? Infos { get; set; }
+
+        [XmlElement("canOpen")]
+        public CanOpen? CanOpen { get; set; }
+
+        [XmlElement("newDat")]
+        public NewDat? NewDat { get; set; }
+
+        [XmlElement("search")]
+        public Search? Search { get; set; }
+
+        [XmlElement("romtitle")]
+        public string? RomTitle { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/Dat.cs b/SabreTools.Models/OfflineList/Dat.cs
new file mode 100644
index 00000000..dd938651
--- /dev/null
+++ b/SabreTools.Models/OfflineList/Dat.cs
@@ -0,0 +1,15 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("dat")]
+    public class Dat
+    {
+        [XmlElement("configuration")]
+        public Configuration? Configuration { get; set; }
+
+        [XmlElement("games")]
+        public Games? Games { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/DatUrl.cs b/SabreTools.Models/OfflineList/DatUrl.cs
new file mode 100644
index 00000000..88b278af
--- /dev/null
+++ b/SabreTools.Models/OfflineList/DatUrl.cs
@@ -0,0 +1,14 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("datURL")]
+    public class DatUrl
+    {
+        [XmlAttribute("fileName")]
+        public string? FileName { get; set; }
+
+        public string? Content { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/FileRomCRC.cs b/SabreTools.Models/OfflineList/FileRomCRC.cs
new file mode 100644
index 00000000..e7bd74f4
--- /dev/null
+++ b/SabreTools.Models/OfflineList/FileRomCRC.cs
@@ -0,0 +1,14 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("romCRC")]
+    public class FileRomCRC
+    {
+        [XmlAttribute("extension")]
+        public string? Extension { get; set; }
+
+        public string? Content { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/Files.cs b/SabreTools.Models/OfflineList/Files.cs
new file mode 100644
index 00000000..dec96125
--- /dev/null
+++ b/SabreTools.Models/OfflineList/Files.cs
@@ -0,0 +1,12 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("files")]
+    public class Files
+    {
+        [XmlElement("romCRC")]
+        public FileRomCRC[]? RomCRC { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/Find.cs b/SabreTools.Models/OfflineList/Find.cs
new file mode 100644
index 00000000..674db9f6
--- /dev/null
+++ b/SabreTools.Models/OfflineList/Find.cs
@@ -0,0 +1,18 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("find")]
+    public class Find
+    {
+        [XmlAttribute("operation")]
+        public string? Operation { get; set; }
+
+        /// <remarks>Numeric?</remarks>
+        [XmlAttribute("value")]
+        public string? Value { get; set; }
+
+        public string? Content { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/Game.cs b/SabreTools.Models/OfflineList/Game.cs
new file mode 100644
index 00000000..9ffd8f8e
--- /dev/null
+++ b/SabreTools.Models/OfflineList/Game.cs
@@ -0,0 +1,51 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("game")]
+    public class Game
+    {
+        [XmlElement("imageNumber")]
+        public string? ImageNumber { get; set; }
+
+        [XmlElement("releaseNumber")]
+        public string? ReleaseNumber { get; set; }
+
+        [XmlElement("title")]
+        public string? Title { get; set; }
+
+        [XmlElement("saveType")]
+        public string? SaveType { get; set; }
+
+        [XmlElement("romSize")]
+        public long? RomSize { get; set; }
+
+        [XmlElement("publisher")]
+        public string? Publisher { get; set; }
+
+        [XmlElement("location")]
+        public string? Location { get; set; }
+
+        [XmlElement("sourceRom")]
+        public string? SourceRom { get; set; }
+
+        [XmlElement("language")]
+        public string? Language { get; set; }
+
+        [XmlElement("files")]
+        public Files? Files { get; set; }
+
+        [XmlElement("im1CRC")]
+        public string? Im1CRC { get; set; }
+
+        [XmlElement("im2CRC")]
+        public string? Im2CRC { get; set; }
+
+        [XmlElement("comment")]
+        public string? Comment { get; set; }
+
+        [XmlElement("duplicateId")]
+        public string? DuplicateID { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/Games.cs b/SabreTools.Models/OfflineList/Games.cs
new file mode 100644
index 00000000..b70ecff4
--- /dev/null
+++ b/SabreTools.Models/OfflineList/Games.cs
@@ -0,0 +1,12 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("games")]
+    public class Games
+    {
+        [XmlElement("game")]
+        public Game[]? Game { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/InfoBase.cs b/SabreTools.Models/OfflineList/InfoBase.cs
new file mode 100644
index 00000000..ffd0c453
--- /dev/null
+++ b/SabreTools.Models/OfflineList/InfoBase.cs
@@ -0,0 +1,56 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    public class InfoBase
+    {
+        [XmlAttribute("visible")]
+        public bool? Visible { get; set; }
+
+        [XmlAttribute("inNamingOption")]
+        public bool? InNamingOption { get; set; }
+
+        [XmlAttribute("default")]
+        public bool? Default { get; set; }
+    }
+
+    [XmlRoot("title")]
+    public class Title : InfoBase { }
+
+    [XmlRoot("location")]
+    public class Location : InfoBase { }
+
+    [XmlRoot("publisher")]
+    public class Publisher : InfoBase { }
+
+    [XmlRoot("sourceRom")]
+    public class SourceRom : InfoBase { }
+
+    [XmlRoot("romSize")]
+    public class RomSize : InfoBase { }
+
+    [XmlRoot("releaseNumber")]
+    public class ReleaseNumber : InfoBase { }
+
+    [XmlRoot("imageNumber")]
+    public class ImageNumber : InfoBase { }
+
+    [XmlRoot("languageNumber")]
+    public class LanguageNumber : InfoBase { }
+
+    [XmlRoot("comment")]
+    public class Comment : InfoBase { }
+
+    [XmlRoot("romCRC")]
+    public class RomCRC : InfoBase { }
+
+    [XmlRoot("im1CRC")]
+    public class Im1CRC : InfoBase { }
+
+    [XmlRoot("im2CRC")]
+    public class Im2CRC : InfoBase { }
+
+    [XmlRoot("languages")]
+    public class Languages : InfoBase { }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/Infos.cs b/SabreTools.Models/OfflineList/Infos.cs
new file mode 100644
index 00000000..aff42cab
--- /dev/null
+++ b/SabreTools.Models/OfflineList/Infos.cs
@@ -0,0 +1,45 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("infos")]
+    public class Infos
+    {
+        [XmlElement("title")]
+        public Title? Title { get; set; }
+
+        [XmlElement("location")]
+        public Location? Location { get; set; }
+
+        [XmlElement("publisher")]
+        public Publisher? Publisher { get; set; }
+
+        [XmlElement("sourceRom")]
+        public SourceRom? SourceRom { get; set; }
+
+        [XmlElement("romSize")]
+        public RomSize? RomSize { get; set; }
+
+        [XmlElement("releaseNumber")]
+        public ReleaseNumber? ReleaseNumber { get; set; }
+
+        [XmlElement("languageNumber")]
+        public LanguageNumber? LanguageNumber { get; set; }
+
+        [XmlElement("comment")]
+        public Comment? Comment { get; set; }
+
+        [XmlElement("romCRC")]
+        public RomCRC? RomCRC { get; set; }
+
+        [XmlElement("im1CRC")]
+        public Im1CRC? Im1CRC { get; set; }
+
+        [XmlElement("im2CRC")]
+        public Im2CRC? Im2CRC { get; set; }
+
+        [XmlElement("languages")]
+        public Languages? Languages { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/NewDat.cs b/SabreTools.Models/OfflineList/NewDat.cs
new file mode 100644
index 00000000..2b89b63f
--- /dev/null
+++ b/SabreTools.Models/OfflineList/NewDat.cs
@@ -0,0 +1,18 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("newDat")]
+    public class NewDat
+    {
+        [XmlElement("datVersionURL")]
+        public string? DatVersionUrl { get; set; }
+
+        [XmlElement("datURL")]
+        public DatUrl? DatUrl { get; set; }
+
+        [XmlElement("imURL")]
+        public string? ImUrl { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/Search.cs b/SabreTools.Models/OfflineList/Search.cs
new file mode 100644
index 00000000..69698bdc
--- /dev/null
+++ b/SabreTools.Models/OfflineList/Search.cs
@@ -0,0 +1,12 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("search")]
+    public class Search
+    {
+        [XmlElement("to")]
+        public To[]? To { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OfflineList/To.cs b/SabreTools.Models/OfflineList/To.cs
new file mode 100644
index 00000000..56bbb60a
--- /dev/null
+++ b/SabreTools.Models/OfflineList/To.cs
@@ -0,0 +1,21 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OfflineList
+{
+    [XmlRoot("to")]
+    public class To
+    {
+        [XmlAttribute("value")]
+        public string? Value { get; set; }
+
+        [XmlAttribute("default")]
+        public bool? Default { get; set; }
+
+        [XmlAttribute("auto")]
+        public bool? Auto { get; set; }
+
+        [XmlElement("find")]
+        public Find[]? Find { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OpenMSX/Dump.cs b/SabreTools.Models/OpenMSX/Dump.cs
new file mode 100644
index 00000000..2c368a4e
--- /dev/null
+++ b/SabreTools.Models/OpenMSX/Dump.cs
@@ -0,0 +1,21 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OpenMSX
+{
+    [XmlRoot("dump")]
+    public class Dump
+    {
+        [XmlElement("original")]
+        public Original? Original { get; set; }
+
+        [XmlElement("rom")]
+        public Rom? Rom { get; set; }
+
+        [XmlElement("megarom")]
+        public MegaRom? MegaRom { get; set; }
+
+        [XmlElement("sccpluscart")]
+        public SCCPlusCart? SCCPlusCart { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OpenMSX/MegaRom.cs b/SabreTools.Models/OpenMSX/MegaRom.cs
new file mode 100644
index 00000000..043b1969
--- /dev/null
+++ b/SabreTools.Models/OpenMSX/MegaRom.cs
@@ -0,0 +1,18 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OpenMSX
+{
+    [XmlRoot("megarom")]
+    public class MegaRom
+    {
+        [XmlElement("type")]
+        public string? Type { get; set; }
+
+        [XmlElement("hash")]
+        public string? Hash { get; set; }
+
+        [XmlElement("remark")]
+        public string? Remark { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OpenMSX/Original.cs b/SabreTools.Models/OpenMSX/Original.cs
new file mode 100644
index 00000000..1ded0f69
--- /dev/null
+++ b/SabreTools.Models/OpenMSX/Original.cs
@@ -0,0 +1,14 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OpenMSX
+{
+    [XmlRoot("original")]
+    public class Original
+    {
+        [XmlElement("value")]
+        public bool Value { get; set; }
+
+        public string? Content { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OpenMSX/Rom.cs b/SabreTools.Models/OpenMSX/Rom.cs
new file mode 100644
index 00000000..a277b2f6
--- /dev/null
+++ b/SabreTools.Models/OpenMSX/Rom.cs
@@ -0,0 +1,21 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OpenMSX
+{
+    [XmlRoot("rom")]
+    public class Rom
+    {
+        [XmlElement("start")]
+        public string? Start { get; set; }
+
+        [XmlElement("type")]
+        public string? Type { get; set; }
+
+        [XmlElement("hash")]
+        public string? Hash { get; set; }
+
+        [XmlElement("remark")]
+        public string? Remark { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OpenMSX/SCCPlusCart.cs b/SabreTools.Models/OpenMSX/SCCPlusCart.cs
new file mode 100644
index 00000000..054abb04
--- /dev/null
+++ b/SabreTools.Models/OpenMSX/SCCPlusCart.cs
@@ -0,0 +1,18 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OpenMSX
+{
+    [XmlRoot("sccpluscart")]
+    public class SCCPlusCart
+    {
+        [XmlElement("boot")]
+        public string? Boot { get; set; }
+
+        [XmlElement("hash")]
+        public string? Hash { get; set; }
+
+        [XmlElement("remark")]
+        public string? Remark { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OpenMSX/Software.cs b/SabreTools.Models/OpenMSX/Software.cs
new file mode 100644
index 00000000..ebbba752
--- /dev/null
+++ b/SabreTools.Models/OpenMSX/Software.cs
@@ -0,0 +1,30 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OpenMSX
+{
+    [XmlRoot("software")]
+    public class Software
+    {
+        [XmlElement("title")]
+        public string Title { get; set; }
+
+        [XmlElement("genmsxid")]
+        public string? GenMSXID { get; set; }
+
+        [XmlElement("system")]
+        public string System { get; set; }
+
+        [XmlElement("company")]
+        public string Company { get; set; }
+
+        [XmlElement("year")]
+        public string Year { get; set; }
+
+        [XmlElement("country")]
+        public string Country { get; set; }
+
+        [XmlElement("dump")]
+        public Dump[]? Dump { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/OpenMSX/SoftwareDb.cs b/SabreTools.Models/OpenMSX/SoftwareDb.cs
new file mode 100644
index 00000000..4341a42c
--- /dev/null
+++ b/SabreTools.Models/OpenMSX/SoftwareDb.cs
@@ -0,0 +1,15 @@
+using System.Xml;
+using System.Xml.Serialization;
+
+namespace SabreTools.Models.OpenMSX
+{
+    [XmlRoot("softwaredb")]
+    public class SoftwareDb
+    {
+        [XmlAttribute("timestamp")]
+        public string? Timestamp { get; set; }
+
+        [XmlAttribute("software")]
+        public Software[]? Software { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/RomCenter/Credits.cs b/SabreTools.Models/RomCenter/Credits.cs
new file mode 100644
index 00000000..565c7db6
--- /dev/null
+++ b/SabreTools.Models/RomCenter/Credits.cs
@@ -0,0 +1,27 @@
+namespace SabreTools.Models.RomCenter
+{
+    /// <remarks>[credits]</remarks>
+    public class Credits
+    {
+        /// <remarks>author</remarks>
+        public string Author { get; set; }
+
+        /// <remarks>version</remarks>
+        public string Version { get; set; }
+
+        /// <remarks>email</remarks>
+        public string Email { get; set; }
+
+        /// <remarks>homepage</remarks>
+        public string Homepage { get; set; }
+
+        /// <remarks>url</remarks>
+        public string Url { get; set; }
+
+        /// <remarks>date</remarks>
+        public string Date { get; set; }
+
+        /// <remarks>comment</remarks>
+        public string Comment { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/RomCenter/Dat.cs b/SabreTools.Models/RomCenter/Dat.cs
new file mode 100644
index 00000000..733ceb62
--- /dev/null
+++ b/SabreTools.Models/RomCenter/Dat.cs
@@ -0,0 +1,18 @@
+namespace SabreTools.Models.RomCenter
+{
+    /// <remarks>[dat]</remarks>
+    public class Dat
+    {
+        /// <remarks>version</remarks>
+        public string Version { get; set; }
+
+        /// <remarks>plugin</remarks>
+        public string Plugin { get; set; }
+
+        /// <remarks>split</remarks>
+        public string Split { get; set; }
+
+        /// <remarks>merge</remarks>
+        public string Merge { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/RomCenter/Emulator.cs b/SabreTools.Models/RomCenter/Emulator.cs
new file mode 100644
index 00000000..cf850d89
--- /dev/null
+++ b/SabreTools.Models/RomCenter/Emulator.cs
@@ -0,0 +1,12 @@
+namespace SabreTools.Models.RomCenter
+{
+    /// <remarks>[emulator]</remarks>
+    public class Emulator
+    {
+        /// <remarks>refname</remarks>
+        public string RefName { get; set; }
+
+        /// <remarks>version</remarks>
+        public string Version { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/RomCenter/Games.cs b/SabreTools.Models/RomCenter/Games.cs
new file mode 100644
index 00000000..12338d48
--- /dev/null
+++ b/SabreTools.Models/RomCenter/Games.cs
@@ -0,0 +1,8 @@
+namespace SabreTools.Models.RomCenter
+{
+    /// <remarks>[games]</remarks>
+    public class Games
+    {
+        public Rom[]? Rom { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/RomCenter/Rom.cs b/SabreTools.Models/RomCenter/Rom.cs
new file mode 100644
index 00000000..3cdcdc2f
--- /dev/null
+++ b/SabreTools.Models/RomCenter/Rom.cs
@@ -0,0 +1,33 @@
+namespace SabreTools.Models.RomCenter
+{
+    /// <remarks>¬-delimited</remarks>
+    public class Rom
+    {
+        /// <remarks>0</remarks>
+        public string? ParentName { get; set; }
+
+        /// <remarks>1</remarks>
+        public string? ParentDescription { get; set; }
+
+        /// <remarks>2</remarks>
+        public string? GameName { get; set; }
+
+        /// <remarks>3</remarks>
+        public string? GameDescription { get; set; }
+
+        /// <remarks>4</remarks>
+        public string? RomName { get; set; }
+
+        /// <remarks>5</remarks>
+        public string? RomCRC { get; set; }
+
+        /// <remarks>6</remarks>
+        public long? RomSize { get; set; }
+
+        /// <remarks>7</remarks>
+        public string? RomOf { get; set; }
+
+        /// <remarks>8</remarks>
+        public string? MergeName { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.Models/SabreTools.Models.csproj b/SabreTools.Models/SabreTools.Models.csproj
index 5d83bbdc..5e3ed4b4 100644
--- a/SabreTools.Models/SabreTools.Models.csproj
+++ b/SabreTools.Models/SabreTools.Models.csproj
@@ -2,6 +2,7 @@
 
   <PropertyGroup>
     <TargetFrameworks>net6.0;net7.0</TargetFrameworks>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
 
 </Project>