diff --git a/CliFx.Analyzers.Tests/CommandSchemaAnalyzerTests.cs b/CliFx.Analyzers.Tests/CommandSchemaAnalyzerTests.cs
index 2d2b0df..c612eb0 100644
--- a/CliFx.Analyzers.Tests/CommandSchemaAnalyzerTests.cs
+++ b/CliFx.Analyzers.Tests/CommandSchemaAnalyzerTests.cs
@@ -164,6 +164,30 @@ public class MyCommand : ICommand
     [CommandParameter(0, Converter = typeof(MyConverter))]
     public string Param { get; set; }
     
+    public ValueTask ExecuteAsync(IConsole console) => default;
+}"
+                )
+            };
+
+            yield return new object[]
+            {
+                new AnalyzerTestCase(
+                    "Parameter with valid validator",
+                    Analyzer.SupportedDiagnostics,
+
+                    // language=cs
+                    @"
+public class MyValidator : ArgumentValueValidator<string>
+{
+    public ValidationResult Validate(string value) => ValidationResult.Ok();
+}
+
+[Command]
+public class MyCommand : ICommand
+{
+    [CommandParameter(0, Validators = new[] {typeof(MyValidator)})]
+    public string Param { get; set; }
+    
     public ValueTask ExecuteAsync(IConsole console) => default;
 }"
                 )
@@ -292,6 +316,30 @@ public class MyCommand : ICommand
     [CommandOption('o', Converter = typeof(MyConverter))]
     public string Option { get; set; }
     
+    public ValueTask ExecuteAsync(IConsole console) => default;
+}"
+                )
+            };
+
+            yield return new object[]
+            {
+                new AnalyzerTestCase(
+                    "Option with valid validator",
+                    Analyzer.SupportedDiagnostics,
+
+                    // language=cs
+                    @"
+public class MyValidator : ArgumentValueValidator<string>
+{
+    public ValidationResult Validate(string value) => ValidationResult.Ok();
+}
+
+[Command]
+public class MyCommand : ICommand
+{
+    [CommandOption('o', Validators = new[] {typeof(MyValidator)})]
+    public string Option { get; set; }
+    
     public ValueTask ExecuteAsync(IConsole console) => default;
 }"
                 )
@@ -438,6 +486,30 @@ public class MyCommand : ICommand
     [CommandParameter(0, Converter = typeof(MyConverter))]
     public string Param { get; set; }
     
+    public ValueTask ExecuteAsync(IConsole console) => default;
+}"
+                )
+            };
+
+            yield return new object[]
+            {
+                new AnalyzerTestCase(
+                    "Parameter with invalid validator",
+                    DiagnosticDescriptors.CliFx0026,
+
+                    // language=cs
+                    @"
+public class MyValidator
+{
+    public ValidationResult Validate(string value) => ValidationResult.Ok();
+}
+
+[Command]
+public class MyCommand : ICommand
+{
+    [CommandParameter(0, Validators = new[] {typeof(MyValidator)})]
+    public string Param { get; set; }
+    
     public ValueTask ExecuteAsync(IConsole console) => default;
 }"
                 )
@@ -566,6 +638,30 @@ public class MyCommand : ICommand
     [CommandOption('o', Converter = typeof(MyConverter))]
     public string Option { get; set; }
     
+    public ValueTask ExecuteAsync(IConsole console) => default;
+}"
+                )
+            };
+
+            yield return new object[]
+            {
+                new AnalyzerTestCase(
+                    "Option with invalid validator",
+                    DiagnosticDescriptors.CliFx0047,
+
+                    // language=cs
+                    @"
+public class MyValidator
+{
+    public ValidationResult Validate(string value) => ValidationResult.Ok();
+}
+
+[Command]
+public class MyCommand : ICommand
+{
+    [CommandOption('o', Validators = new[] {typeof(MyValidator)})]
+    public string Option { get; set; }
+    
     public ValueTask ExecuteAsync(IConsole console) => default;
 }"
                 )
diff --git a/CliFx.Analyzers/CommandSchemaAnalyzer.cs b/CliFx.Analyzers/CommandSchemaAnalyzer.cs
index cf652fb..5c0a307 100644
--- a/CliFx.Analyzers/CommandSchemaAnalyzer.cs
+++ b/CliFx.Analyzers/CommandSchemaAnalyzer.cs
@@ -18,12 +18,14 @@ namespace CliFx.Analyzers
             DiagnosticDescriptors.CliFx0023,
             DiagnosticDescriptors.CliFx0024,
             DiagnosticDescriptors.CliFx0025,
+            DiagnosticDescriptors.CliFx0026,
             DiagnosticDescriptors.CliFx0041,
             DiagnosticDescriptors.CliFx0042,
             DiagnosticDescriptors.CliFx0043,
             DiagnosticDescriptors.CliFx0044,
             DiagnosticDescriptors.CliFx0045,
-            DiagnosticDescriptors.CliFx0046
+            DiagnosticDescriptors.CliFx0046,
+            DiagnosticDescriptors.CliFx0047
         );
 
         private static bool IsScalarType(ITypeSymbol typeSymbol) =>
@@ -57,14 +59,24 @@ namespace CliFx.Analyzers
                         .NamedArguments
                         .Where(a => a.Key == "Converter")
                         .Select(a => a.Value.Value)
-                        .FirstOrDefault() as ITypeSymbol;
+                        .Cast<ITypeSymbol?>()
+                        .FirstOrDefault();
+
+                    var validators = attribute
+                        .NamedArguments
+                        .Where(a => a.Key == "Validators")
+                        .SelectMany(a => a.Value.Values)
+                        .Select(c => c.Value)
+                        .Cast<ITypeSymbol>()
+                        .ToArray();
 
                     return new
                     {
                         Property = p,
                         Order = order,
                         Name = name,
-                        Converter = converter
+                        Converter = converter,
+                        Validators = validators
                     };
                 })
                 .ToArray();
@@ -140,6 +152,18 @@ namespace CliFx.Analyzers
                     DiagnosticDescriptors.CliFx0025, parameter.Property.Locations.First()
                 ));
             }
+
+            // Invalid validators
+            var invalidValidatorsParameters = parameters
+                .Where(p => !p.Validators.All(v => v.AllInterfaces.Any(KnownSymbols.IsArgumentValueValidatorInterface)))
+                .ToArray();
+
+            foreach (var parameter in invalidValidatorsParameters)
+            {
+                context.ReportDiagnostic(Diagnostic.Create(
+                    DiagnosticDescriptors.CliFx0026, parameter.Property.Locations.First()
+                ));
+            }
         }
 
         private static void CheckCommandOptionProperties(
@@ -175,7 +199,16 @@ namespace CliFx.Analyzers
                         .NamedArguments
                         .Where(a => a.Key == "Converter")
                         .Select(a => a.Value.Value)
-                        .FirstOrDefault() as ITypeSymbol;
+                        .Cast<ITypeSymbol>()
+                        .FirstOrDefault();
+
+                    var validators = attribute
+                        .NamedArguments
+                        .Where(a => a.Key == "Validators")
+                        .SelectMany(a => a.Value.Values)
+                        .Select(c => c.Value)
+                        .Cast<ITypeSymbol>()
+                        .ToArray();
 
                     return new
                     {
@@ -183,7 +216,8 @@ namespace CliFx.Analyzers
                         Name = name,
                         ShortName = shortName,
                         EnvironmentVariableName = envVarName,
-                        Converter = converter
+                        Converter = converter,
+                        Validators = validators
                     };
                 })
                 .ToArray();
@@ -270,6 +304,18 @@ namespace CliFx.Analyzers
                     DiagnosticDescriptors.CliFx0046, option.Property.Locations.First()
                 ));
             }
+
+            // Invalid validators
+            var invalidValidatorsOptions = options
+                .Where(p => !p.Validators.All(v => v.AllInterfaces.Any(KnownSymbols.IsArgumentValueValidatorInterface)))
+                .ToArray();
+
+            foreach (var option in invalidValidatorsOptions)
+            {
+                context.ReportDiagnostic(Diagnostic.Create(
+                    DiagnosticDescriptors.CliFx0047, option.Property.Locations.First()
+                ));
+            }
         }
 
         private static void CheckCommandType(SymbolAnalysisContext context)
diff --git a/CliFx.Analyzers/DiagnosticDescriptors.cs b/CliFx.Analyzers/DiagnosticDescriptors.cs
index d6a20d4..7da2dff 100644
--- a/CliFx.Analyzers/DiagnosticDescriptors.cs
+++ b/CliFx.Analyzers/DiagnosticDescriptors.cs
@@ -53,6 +53,13 @@ namespace CliFx.Analyzers
                 "Usage", DiagnosticSeverity.Error, true
             );
 
+        public static readonly DiagnosticDescriptor CliFx0026 =
+            new DiagnosticDescriptor(nameof(CliFx0026),
+                "Parameter validator must implement 'CliFx.ArgumentValueValidator<T>'",
+                "Parameter validator must implement 'CliFx.ArgumentValueValidator<T>'",
+                "Usage", DiagnosticSeverity.Error, true
+            );
+
         public static readonly DiagnosticDescriptor CliFx0041 =
             new DiagnosticDescriptor(nameof(CliFx0041),
                 "Option must have a name or short name specified",
@@ -95,6 +102,13 @@ namespace CliFx.Analyzers
                 "Usage", DiagnosticSeverity.Error, true
             );
 
+        public static readonly DiagnosticDescriptor CliFx0047 =
+            new DiagnosticDescriptor(nameof(CliFx0047),
+                "Option validator must implement 'CliFx.ArgumentValueValidator<T>'",
+                "Option validator must implement 'CliFx.ArgumentValueValidator<T>'",
+                "Usage", DiagnosticSeverity.Error, true
+            );
+
         public static readonly DiagnosticDescriptor CliFx0100 =
             new DiagnosticDescriptor(nameof(CliFx0100),
                 "Use the provided IConsole abstraction instead of System.Console to ensure that the command can be tested in isolation",
diff --git a/CliFx.Analyzers/KnownSymbols.cs b/CliFx.Analyzers/KnownSymbols.cs
index 2510d47..329a0a4 100644
--- a/CliFx.Analyzers/KnownSymbols.cs
+++ b/CliFx.Analyzers/KnownSymbols.cs
@@ -28,6 +28,9 @@ namespace CliFx.Analyzers
         public static bool IsArgumentValueConverterInterface(ISymbol symbol) =>
             symbol.DisplayNameMatches("CliFx.IArgumentValueConverter");
 
+        public static bool IsArgumentValueValidatorInterface(ISymbol symbol) =>
+            symbol.DisplayNameMatches("CliFx.IArgumentValueValidator");
+
         public static bool IsCommandAttribute(ISymbol symbol) =>
             symbol.DisplayNameMatches("CliFx.Attributes.CommandAttribute");