diff --git a/SabreTools.IO.Extensions.Test/IOExtensionsTests.cs b/SabreTools.IO.Extensions.Test/IOExtensionsTests.cs
index d2c4314..0a60166 100644
--- a/SabreTools.IO.Extensions.Test/IOExtensionsTests.cs
+++ b/SabreTools.IO.Extensions.Test/IOExtensionsTests.cs
@@ -369,29 +369,60 @@ namespace SabreTools.IO.Extensions.Test
         // TODO: Add tests for home path without modifying the runner's home path
 
         [Fact]
-        public void ResolvePath_AbsolutePath_Exists_ReturnsAsIs()
+        public void ResolvePath_AbsolutePath_Exists_ReturnsFullPath()
         {
-            string path = typeof(IOExtensionsTests).Assembly.Location;
+            string filename = Guid.NewGuid().ToString();
+            string path = Path.Combine(Environment.CurrentDirectory, filename);
 
-            string? actual = path.ResolvePath();
-            Assert.Equal(path, actual);
+            File.WriteAllBytes(path, []);
+            try
+            {
+                string? actual = filename.ResolvePath();
+                Assert.Equal(path, actual);
+            }
+            finally
+            {
+                File.Delete(path);
+            }
         }
 
         [Fact]
         public void ResolvePath_AbsolutePath_Missing_ReturnsNull()
         {
-            string path = Path.Combine(Path.GetTempPath(), "fake-path.bin");
+            string filename = Guid.NewGuid().ToString();
+            string path = Path.Combine(Environment.CurrentDirectory, filename);
 
             string? actual = path.ResolvePath();
             Assert.Null(actual);
         }
 
-        // TODO: Add ResolvePath_RelativePath_Exists_ReturnsAsIs
+        [Fact]
+        public void ResolvePath_RelativePath_Exists_ReturnsFullPath()
+        {
+            string filename = Guid.NewGuid().ToString();
+            string subDir = "RELATIVE";
+            string path = Path.Combine(subDir, filename);
+            string expected = Path.Combine(Environment.CurrentDirectory, path);
+
+            Directory.CreateDirectory(subDir);
+            File.WriteAllBytes(path, []);
+            try
+            {
+                string? actual = path.ResolvePath();
+                Assert.Equal(expected, actual);
+            }
+            finally
+            {
+                Directory.Delete(subDir, recursive: true);
+            }
+        }
 
         [Fact]
         public void ResolvePath_RelativePath_Missing_ReturnsNull()
         {
-            string path = Path.Combine("INVALID", "fake-path.bin");
+            string filename = Guid.NewGuid().ToString();
+            string subDir = "INVALID";
+            string path = Path.Combine(subDir, filename);
 
             string? actual = path.ResolvePath();
             Assert.Null(actual);
@@ -400,8 +431,7 @@ namespace SabreTools.IO.Extensions.Test
         [Fact]
         public void ResolvePath_BareName_RuntimeDirectory_ReturnsFullPath()
         {
-            // Create a file in the test assembly's runtime directory
-            string filename = "fake-path.bin";
+            string filename = Guid.NewGuid().ToString();
             string path = Path.Combine(AppContext.BaseDirectory, filename);
 
             File.WriteAllBytes(path, []);
@@ -419,13 +449,12 @@ namespace SabreTools.IO.Extensions.Test
         [Fact]
         public void ResolvePath_BareName_Path_ReturnsFullPath()
         {
-            // Create a temporary directory for testing
-            string tempDir = Path.Combine(Path.GetTempPath(), "fake-path");
-            Directory.CreateDirectory(tempDir);
+            string filename = Guid.NewGuid().ToString();
+            string subDir = Path.GetFullPath("TEMP");
+            string path = Path.Combine(subDir, filename);
+            string expected = Path.Combine(Environment.CurrentDirectory, path);
 
-            // Create a file in the temporary directory
-            string filename = "fake-path.bin";
-            string path = Path.Combine(tempDir, filename);
+            Directory.CreateDirectory(subDir);
             File.WriteAllBytes(path, []);
 
             // Prepend the temp directory to PATH and check it exists
@@ -433,21 +462,21 @@ namespace SabreTools.IO.Extensions.Test
             string? originalPath = Environment.GetEnvironmentVariable("PATH");
             try
             {
-                Environment.SetEnvironmentVariable("PATH", tempDir + Path.PathSeparator + (originalPath ?? string.Empty));
+                Environment.SetEnvironmentVariable("PATH", subDir + Path.PathSeparator + (originalPath ?? string.Empty));
                 string? actual = filename.ResolvePath();
-                Assert.Equal(path, actual);
+                Assert.Equal(expected, actual);
             }
             finally
             {
                 Environment.SetEnvironmentVariable("PATH", originalPath);
-                Directory.Delete(tempDir, recursive: true);
+                Directory.Delete(subDir, recursive: true);
             }
         }
 
         [Fact]
         public void ResolvePath_BareName_Missing_ReturnsNull()
         {
-            string filename = "fake-path.bin";
+            string filename = Guid.NewGuid().ToString();
 
             string? actual = filename.ResolvePath();
             Assert.Null(actual);
diff --git a/SabreTools.IO.Extensions/IOExtensions.cs b/SabreTools.IO.Extensions/IOExtensions.cs
index f918346..e508f43 100644
--- a/SabreTools.IO.Extensions/IOExtensions.cs
+++ b/SabreTools.IO.Extensions/IOExtensions.cs
@@ -419,15 +419,11 @@ namespace SabreTools.IO.Extensions
         }
 
         /// <summary>
-        /// Resolve a file path that may be relative or contained within a PATH directory.
+        /// Resolve a file path that may be absolute, relative,
+        /// within the runtime directory, or contained within a PATH directory.
         /// </summary>
         /// <param name="path">Raw value from the user's options</param>
         /// <returns>The absolute path of the located files, or null on failure</returns>
-        /// <remarks>
-        /// A value containing a path separator is treated as an explicit location and
-        /// returned as-is when it exists. A bare name (no separator) is searched in the
-        /// runtime directory first, then in each PATH entry.
-        /// </remarks>
         public static string? ResolvePath(this string? path)
         {
             // Invalid paths always return null
@@ -442,12 +438,12 @@ namespace SabreTools.IO.Extensions
                 path = path.Substring(2);
                 path = Path.Combine(homeDirectory, path);
 
-                return File.Exists(path) ? path : null;
+                return File.Exists(path) ? Path.GetFullPath(path) : null;
             }
 
             // Explicit location (absolute or relative path)
             if (path.Contains("/") || path.Contains("\\"))
-                return File.Exists(path) ? path : null;
+                return File.Exists(path) ? Path.GetFullPath(path) : null;
 
             // Check the runtime directory if no directory path is provided
             string runtimeDir = PathTool.GetRuntimeDirectory();
@@ -940,7 +936,7 @@ namespace SabreTools.IO.Extensions
         private static EnumerationOptions FromSearchOption(SearchOption searchOption)
         {
             if ((searchOption != SearchOption.TopDirectoryOnly) && (searchOption != SearchOption.AllDirectories))
-                throw new System.ArgumentOutOfRangeException(nameof(searchOption));
+                throw new ArgumentOutOfRangeException(nameof(searchOption));
 
             return searchOption == SearchOption.AllDirectories
                 ? new EnumerationOptions { RecurseSubdirectories = true, MatchType = MatchType.Win32, AttributesToSkip = 0, IgnoreInaccessible = false }