diff --git a/SabreTools.Library/DatFiles/Json.cs b/SabreTools.Library/DatFiles/Json.cs
index b2ba4257..6cea3d38 100644
--- a/SabreTools.Library/DatFiles/Json.cs
+++ b/SabreTools.Library/DatFiles/Json.cs
@@ -623,6 +623,20 @@ namespace SabreTools.Library.DatFiles
 
                     #endregion
 
+                    #region OpenMSX
+
+                    case "genmsxid":
+                        machine.GenMSXID = jtr.ReadAsString();
+                        break;
+                    case "system":
+                        machine.System = jtr.ReadAsString();
+                        break;
+                    case "country":
+                        machine.Country = jtr.ReadAsString();
+                        break;
+
+                    #endregion
+
                     #region SoftwareList
 
                     case "supported":
@@ -1758,6 +1772,26 @@ namespace SabreTools.Library.DatFiles
 
                 #endregion
 
+                #region OpenMSX
+
+                if (!string.IsNullOrWhiteSpace(datItem.GetField(Field.GenMSXID, Header.ExcludeFields)))
+                {
+                    jtw.WritePropertyName("genmsxid");
+                    jtw.WriteValue(datItem.Machine.GenMSXID);
+                }
+                if (!string.IsNullOrWhiteSpace(datItem.GetField(Field.System, Header.ExcludeFields)))
+                {
+                    jtw.WritePropertyName("system");
+                    jtw.WriteValue(datItem.Machine.System);
+                }
+                if (!string.IsNullOrWhiteSpace(datItem.GetField(Field.Country, Header.ExcludeFields)))
+                {
+                    jtw.WritePropertyName("country");
+                    jtw.WriteValue(datItem.Machine.Country);
+                }
+
+                #endregion
+
                 #region SoftwareList
 
                 if (!Header.ExcludeFields.Contains(Field.Supported) && datItem.Machine.Supported != null)
diff --git a/SabreTools.Library/DatFiles/OpenMSX.cs b/SabreTools.Library/DatFiles/OpenMSX.cs
index 138b8485..2ff84a44 100644
--- a/SabreTools.Library/DatFiles/OpenMSX.cs
+++ b/SabreTools.Library/DatFiles/OpenMSX.cs
@@ -135,13 +135,11 @@ namespace SabreTools.Library.DatFiles
                         break;
 
                     case "genmsxid":
-                        // string id = reader.ReadElementContentAsString();
-                        reader.Read();
+                        machine.GenMSXID = reader.ReadElementContentAsString();
                         break;
 
                     case "system":
-                        // string system = reader.ReadElementContentAsString();
-                        reader.Read();
+                        machine.System = reader.ReadElementContentAsString();
                         break;
 
                     case "company":
@@ -153,8 +151,7 @@ namespace SabreTools.Library.DatFiles
                         break;
 
                     case "country":
-                        // string country = reader.ReadElementContentAsString();
-                        reader.Read();
+                        machine.Country = reader.ReadElementContentAsString();
                         break;
 
                     case "dump":
@@ -631,11 +628,11 @@ namespace SabreTools.Library.DatFiles
                 // Build the state based on excluded fields
                 xtw.WriteStartElement("software");
                 xtw.WriteElementString("title", datItem.GetField(Field.MachineName, Header.ExcludeFields));
-                //xtw.WriteElementString("genmsxid", msxid);
-                //xtw.WriteElementString("system", system));
+                xtw.WriteElementString("genmsxid", datItem.GetField(Field.GenMSXID, Header.ExcludeFields));
+                xtw.WriteElementString("system", datItem.GetField(Field.System, Header.ExcludeFields));
                 xtw.WriteElementString("company", datItem.GetField(Field.Manufacturer, Header.ExcludeFields));
                 xtw.WriteElementString("year", datItem.GetField(Field.Year, Header.ExcludeFields));
-                //xtw.WriteElementString("country", country);
+                xtw.WriteElementString("country", datItem.GetField(Field.Country, Header.ExcludeFields));
 
                 xtw.Flush();
             }
diff --git a/SabreTools.Library/DatFiles/SeparatedValue.cs b/SabreTools.Library/DatFiles/SeparatedValue.cs
index b380827c..8dab7466 100644
--- a/SabreTools.Library/DatFiles/SeparatedValue.cs
+++ b/SabreTools.Library/DatFiles/SeparatedValue.cs
@@ -459,6 +459,22 @@ namespace SabreTools.Library.DatFiles
 
                         #endregion
 
+                        #region OpenMSX
+
+                        case "Machine.GenMSXID":
+                            machine.GenMSXID = value;
+                            break;
+
+                        case "Machine.System":
+                            machine.System = value;
+                            break;
+
+                        case "Machine.Country":
+                            machine.Country = value;
+                            break;
+
+                        #endregion
+
                         #region SoftwareList
 
                         case "Machine.Supported":
@@ -1238,6 +1254,25 @@ namespace SabreTools.Library.DatFiles
 
                 #endregion
 
+                #region OpenMSX
+
+                case "genmsxid":
+                case "genmsx id":
+                case "genmsx-id":
+                case "gen msx id":
+                case "gen-msx-id":
+                    return "Machine.GenMSXID";
+
+                case "msxsystem":
+                case "msx system":
+                case "msx-system":
+                    return "Machine.System";
+
+                case "country":
+                    return "Machine.Country";
+
+                #endregion
+
                 #region SoftwareList
 
                 case "supported":
diff --git a/SabreTools.Library/DatItems/DatItem.cs b/SabreTools.Library/DatItems/DatItem.cs
index ec0bd2eb..61f0beb3 100644
--- a/SabreTools.Library/DatItems/DatItem.cs
+++ b/SabreTools.Library/DatItems/DatItem.cs
@@ -251,6 +251,11 @@ namespace SabreTools.Library.DatItems
             Field.HasCrc,
             Field.RelatedTo,
 
+            // OpenMSX
+            Field.GenMSXID,
+            Field.System,
+            Field.Country,
+
             // SoftwareList
             Field.Supported,
             Field.SharedFeatures,
diff --git a/SabreTools.Library/DatItems/Enums.cs b/SabreTools.Library/DatItems/Enums.cs
index 9d923def..060a5da4 100644
--- a/SabreTools.Library/DatItems/Enums.cs
+++ b/SabreTools.Library/DatItems/Enums.cs
@@ -87,6 +87,14 @@ namespace SabreTools.Library.DatItems
 
         #endregion
 
+        #region OpenMSX
+
+        GenMSXID,
+        System,
+        Country,
+
+        #endregion
+
         #region SoftwareList
 
         Supported,
diff --git a/SabreTools.Library/DatItems/Machine.cs b/SabreTools.Library/DatItems/Machine.cs
index 4cba6c45..07b49a79 100644
--- a/SabreTools.Library/DatItems/Machine.cs
+++ b/SabreTools.Library/DatItems/Machine.cs
@@ -3,8 +3,8 @@ using System.Collections.Generic;
 using System.Linq;
 
 using SabreTools.Library.Filtering;
-using Newtonsoft.Json;
 using SabreTools.Library.Tools;
+using Newtonsoft.Json;
 
 namespace SabreTools.Library.DatItems
 {
@@ -245,6 +245,28 @@ namespace SabreTools.Library.DatItems
 
         #endregion
 
+        #region OpenMSX Fields
+
+        /// <summary>
+        /// Generation MSX ID
+        /// </summary>
+        [JsonProperty("genmsxid")]
+        public string GenMSXID { get; set; } = null;
+
+        /// <summary>
+        /// MSX System
+        /// </summary>
+        [JsonProperty("system")]
+        public string System { get; set; } = null;
+
+        /// <summary>
+        /// Machine country of origin
+        /// </summary>
+        [JsonProperty("country")]
+        public string Country { get; set; } = null;
+
+        #endregion
+
         #region SoftwareList Fields
 
         /// <summary>
@@ -412,6 +434,20 @@ namespace SabreTools.Library.DatItems
 
                 #endregion
 
+                #region OpenMSX
+
+                case Field.GenMSXID:
+                    fieldValue = GenMSXID;
+                    break;
+                case Field.System:
+                    fieldValue = System;
+                    break;
+                case Field.Country:
+                    fieldValue = Country;
+                    break;
+
+                #endregion
+
                 #region SoftwareList
 
                 case Field.Supported:
@@ -588,6 +624,19 @@ namespace SabreTools.Library.DatItems
 
             #endregion
 
+            #region OpenMSX
+
+            if (mappings.Keys.Contains(Field.GenMSXID))
+                GenMSXID = mappings[Field.GenMSXID];
+
+            if (mappings.Keys.Contains(Field.System))
+                System = mappings[Field.System];
+
+            if (mappings.Keys.Contains(Field.Country))
+                Country = mappings[Field.Country];
+
+            #endregion
+
             #region SoftwareList
 
             if (mappings.Keys.Contains(Field.Supported))
@@ -710,6 +759,14 @@ namespace SabreTools.Library.DatItems
 
                 #endregion
 
+                #region OpenMSX
+
+                GenMSXID = this.GenMSXID,
+                System = this.System,
+                Country = this.Country,
+
+                #endregion
+
                 #region SoftwareList
 
                 Supported = this.Supported,
@@ -976,6 +1033,28 @@ namespace SabreTools.Library.DatItems
 
             #endregion
 
+            #region OpenMSX
+
+            // Filter on Generation MSX ID
+            if (filter.GenMSXID.MatchesPositiveSet(GenMSXID) == false)
+                return false;
+            if (filter.GenMSXID.MatchesNegativeSet(GenMSXID) == true)
+                return false;
+
+            // Filter on system
+            if (filter.System.MatchesPositiveSet(System) == false)
+                return false;
+            if (filter.System.MatchesNegativeSet(System) == true)
+                return false;
+
+            // Filter on country
+            if (filter.Country.MatchesPositiveSet(Country) == false)
+                return false;
+            if (filter.Country.MatchesNegativeSet(Country) == true)
+                return false;
+
+            #endregion
+
             #region SoftwareList
 
             // Filter on supported
@@ -1115,6 +1194,19 @@ namespace SabreTools.Library.DatItems
 
             #endregion
 
+            #region OpenMSX
+
+            if (fields.Contains(Field.GenMSXID))
+                GenMSXID = null;
+
+            if (fields.Contains(Field.System))
+                System = null;
+
+            if (fields.Contains(Field.Country))
+                Country = null;
+
+            #endregion
+
             #region SoftwareList
 
             if (fields.Contains(Field.Supported))
@@ -1266,6 +1358,19 @@ namespace SabreTools.Library.DatItems
 
             #endregion
 
+            #region OpenMSX
+
+            if (fields.Contains(Field.GenMSXID))
+                GenMSXID = machine.GenMSXID;
+
+            if (fields.Contains(Field.System))
+                System = machine.System;
+
+            if (fields.Contains(Field.Country))
+                Country = machine.Country;
+
+            #endregion
+
             #region SoftwareList
 
             if (fields.Contains(Field.Supported))
diff --git a/SabreTools.Library/Filtering/Filter.cs b/SabreTools.Library/Filtering/Filter.cs
index 6a9511b7..67034fe6 100644
--- a/SabreTools.Library/Filtering/Filter.cs
+++ b/SabreTools.Library/Filtering/Filter.cs
@@ -205,6 +205,25 @@ namespace SabreTools.Library.Filtering
 
         #endregion
 
+        #region OpenMSX
+
+        /// <summary>
+        /// Include or exclude machine Generation MSX ID
+        /// </summary>
+        public FilterItem<string> GenMSXID { get; private set; } = new FilterItem<string>();
+
+        /// <summary>
+        /// Include or exclude machine system
+        /// </summary>
+        public FilterItem<string> System { get; private set; } = new FilterItem<string>();
+
+        /// <summary>
+        /// Include or exclude machine country
+        /// </summary>
+        public FilterItem<string> Country { get; private set; } = new FilterItem<string>();
+
+        #endregion
+
         #region SoftwareList
 
         /// <summary>
@@ -762,6 +781,31 @@ namespace SabreTools.Library.Filtering
 
                 #endregion
 
+                #region OpenMSX
+
+                case Field.GenMSXID:
+                    if (negate)
+                        GenMSXID.NegativeSet.Add(value);
+                    else
+                        GenMSXID.PositiveSet.Add(value);
+                    break;
+
+                case Field.System:
+                    if (negate)
+                        System.NegativeSet.Add(value);
+                    else
+                        System.PositiveSet.Add(value);
+                    break;
+
+                case Field.Country:
+                    if (negate)
+                        Country.NegativeSet.Add(value);
+                    else
+                        Country.PositiveSet.Add(value);
+                    break;
+
+                #endregion
+
                 #region SoftwareList
 
                 case Field.Supported:
diff --git a/SabreTools.Library/Tools/Converters.cs b/SabreTools.Library/Tools/Converters.cs
index 22e41e85..d0e75663 100644
--- a/SabreTools.Library/Tools/Converters.cs
+++ b/SabreTools.Library/Tools/Converters.cs
@@ -293,6 +293,26 @@ namespace SabreTools.Library.Tools
 
                 #endregion
 
+                #region OpenMSX
+
+                case "genmsxid":
+                case "genmsx id":
+                case "genmsx-id":
+                case "gen msx id":
+                case "gen-msx-id":
+                    return Field.GenMSXID;
+
+                case "system":
+                case "msxsystem":
+                case "msx system":
+                case "msx-system":
+                    return Field.System;
+
+                case "country":
+                    return Field.Country;
+
+                #endregion
+
                 #region SoftwareList
 
                 case "supported":