diff --git a/X86DisassemblerTests/DataTransferInstructionTests.cs b/X86DisassemblerTests/DataTransferInstructionTests.cs
new file mode 100644
index 0000000..a90b2fc
--- /dev/null
+++ b/X86DisassemblerTests/DataTransferInstructionTests.cs
@@ -0,0 +1,175 @@
+namespace X86DisassemblerTests;
+
+using System;
+using Xunit;
+using X86Disassembler.X86;
+using X86Disassembler.X86.Handlers;
+
+/// <summary>
+/// Tests for data transfer instruction handlers
+/// </summary>
+public class DataTransferInstructionTests
+{
+    /// <summary>
+    /// Tests the DataTransferHandler for decoding MOV r32, r/m32 instruction
+    /// </summary>
+    [Fact]
+    public void DataTransferHandler_DecodesMovR32Rm32_Correctly()
+    {
+        // Arrange
+        // MOV EAX, ECX (8B C1) - ModR/M byte C1 = 11 000 001 (mod=3, reg=0, rm=1)
+        // mod=3 means direct register addressing, reg=0 is EAX, rm=1 is ECX
+        byte[] codeBuffer = new byte[] { 0x8B, 0xC1 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("mov", instruction.Mnemonic);
+        Assert.Equal("ecx, eax", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the DataTransferHandler for decoding MOV r/m32, r32 instruction
+    /// </summary>
+    [Fact]
+    public void DataTransferHandler_DecodesMovRm32R32_Correctly()
+    {
+        // Arrange
+        // MOV ECX, EAX (89 C1) - ModR/M byte C1 = 11 000 001 (mod=3, reg=0, rm=1)
+        // mod=3 means direct register addressing, reg=0 is EAX, rm=1 is ECX
+        byte[] codeBuffer = new byte[] { 0x89, 0xC1 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("mov", instruction.Mnemonic);
+        Assert.Equal("eax, ecx", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the DataTransferHandler for decoding MOV r32, imm32 instruction
+    /// </summary>
+    [Fact]
+    public void DataTransferHandler_DecodesMovR32Imm32_Correctly()
+    {
+        // Arrange
+        // MOV EAX, 0x12345678 (B8 78 56 34 12)
+        byte[] codeBuffer = new byte[] { 0xB8, 0x78, 0x56, 0x34, 0x12 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("mov", instruction.Mnemonic);
+        Assert.Equal("eax, 0x12345678", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the DataTransferHandler for decoding MOV EAX, moffs32 instruction
+    /// </summary>
+    [Fact]
+    public void DataTransferHandler_DecodesMovEaxMoffs32_Correctly()
+    {
+        // Arrange
+        // MOV EAX, [0x12345678] (A1 78 56 34 12)
+        byte[] codeBuffer = new byte[] { 0xA1, 0x78, 0x56, 0x34, 0x12 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("mov", instruction.Mnemonic);
+        Assert.Equal("eax, [0x12345678]", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the DataTransferHandler for decoding MOV moffs32, EAX instruction
+    /// </summary>
+    [Fact]
+    public void DataTransferHandler_DecodesMovMoffs32Eax_Correctly()
+    {
+        // Arrange
+        // MOV [0x12345678], EAX (A3 78 56 34 12)
+        byte[] codeBuffer = new byte[] { 0xA3, 0x78, 0x56, 0x34, 0x12 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("mov", instruction.Mnemonic);
+        Assert.Equal("[0x12345678], eax", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the DataTransferHandler for decoding MOV with memory addressing
+    /// </summary>
+    [Fact]
+    public void DataTransferHandler_DecodesMovWithMemoryAddressing_Correctly()
+    {
+        // Arrange
+        // MOV EAX, [ECX+0x12345678] (8B 81 78 56 34 12) - ModR/M byte 81 = 10 000 001 (mod=2, reg=0, rm=1)
+        // mod=2 means memory addressing with 32-bit displacement, reg=0 is EAX, rm=1 is ECX
+        byte[] codeBuffer = new byte[] { 0x8B, 0x81, 0x78, 0x56, 0x34, 0x12 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("mov", instruction.Mnemonic);
+        Assert.Equal("dword ptr [ecx+0x12345678], eax", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the DataTransferHandler for decoding PUSH r32 instruction
+    /// </summary>
+    [Fact]
+    public void DataTransferHandler_DecodesPushR32_Correctly()
+    {
+        // Arrange
+        // PUSH EAX (50)
+        byte[] codeBuffer = new byte[] { 0x50 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("push", instruction.Mnemonic);
+        Assert.Equal("eax", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the DataTransferHandler for decoding POP r32 instruction
+    /// </summary>
+    [Fact]
+    public void DataTransferHandler_DecodesPopR32_Correctly()
+    {
+        // Arrange
+        // POP ECX (59)
+        byte[] codeBuffer = new byte[] { 0x59 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("pop", instruction.Mnemonic);
+        Assert.Equal("ecx", instruction.Operands);
+    }
+}
diff --git a/X86DisassemblerTests/Group1InstructionTests.cs b/X86DisassemblerTests/Group1InstructionTests.cs
index 285ee5b..111a905 100644
--- a/X86DisassemblerTests/Group1InstructionTests.cs
+++ b/X86DisassemblerTests/Group1InstructionTests.cs
@@ -114,4 +114,176 @@ public class Group1InstructionTests
         Assert.Equal("cmp", instruction.Mnemonic);
         Assert.Equal("ebx, 0x12345678", instruction.Operands);
     }
+    
+    /// <summary>
+    /// Tests the AdcImmToRm32Handler for decoding ADC r/m32, imm32 instruction
+    /// </summary>
+    [Fact]
+    public void AdcImmToRm32Handler_DecodesAdcRm32Imm32_Correctly()
+    {
+        // Arrange
+        // ADC ECX, 0x12345678 (81 D1 78 56 34 12) - ModR/M byte D1 = 11 010 001 (mod=3, reg=2, rm=1)
+        // mod=3 means direct register addressing, reg=2 indicates ADC operation, rm=1 is ECX
+        byte[] codeBuffer = new byte[] { 0x81, 0xD1, 0x78, 0x56, 0x34, 0x12 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("adc", instruction.Mnemonic);
+        Assert.Equal("ecx, 0x12345678", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the AdcImmToRm32SignExtendedHandler for decoding ADC r/m32, imm8 instruction (sign-extended)
+    /// </summary>
+    [Fact]
+    public void AdcImmToRm32SignExtendedHandler_DecodesAdcRm32Imm8_Correctly()
+    {
+        // Arrange
+        // ADC ECX, 0x42 (83 D1 42) - ModR/M byte D1 = 11 010 001 (mod=3, reg=2, rm=1)
+        // mod=3 means direct register addressing, reg=2 indicates ADC operation, rm=1 is ECX
+        // The immediate value 0x42 is sign-extended to 32 bits
+        byte[] codeBuffer = new byte[] { 0x83, 0xD1, 0x42 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("adc", instruction.Mnemonic);
+        Assert.Equal("ecx, 0x00000042", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the SbbImmFromRm32Handler for decoding SBB r/m32, imm32 instruction
+    /// </summary>
+    [Fact]
+    public void SbbImmFromRm32Handler_DecodesSbbRm32Imm32_Correctly()
+    {
+        // Arrange
+        // SBB EDX, 0x12345678 (81 DA 78 56 34 12) - ModR/M byte DA = 11 011 010 (mod=3, reg=3, rm=2)
+        // mod=3 means direct register addressing, reg=3 indicates SBB operation, rm=2 is EDX
+        byte[] codeBuffer = new byte[] { 0x81, 0xDA, 0x78, 0x56, 0x34, 0x12 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("sbb", instruction.Mnemonic);
+        Assert.Equal("edx, 0x12345678", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the SbbImmFromRm32SignExtendedHandler for decoding SBB r/m32, imm8 instruction (sign-extended)
+    /// </summary>
+    [Fact]
+    public void SbbImmFromRm32SignExtendedHandler_DecodesSbbRm32Imm8_Correctly()
+    {
+        // Arrange
+        // SBB EDX, 0x42 (83 DA 42) - ModR/M byte DA = 11 011 010 (mod=3, reg=3, rm=2)
+        // mod=3 means direct register addressing, reg=3 indicates SBB operation, rm=2 is EDX
+        // The immediate value 0x42 is sign-extended to 32 bits
+        byte[] codeBuffer = new byte[] { 0x83, 0xDA, 0x42 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("sbb", instruction.Mnemonic);
+        Assert.Equal("edx, 0x00000042", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the AndImmWithRm32Handler for decoding AND r/m32, imm32 instruction
+    /// </summary>
+    [Fact]
+    public void AndImmWithRm32Handler_DecodesAndRm32Imm32_Correctly()
+    {
+        // Arrange
+        // AND EBX, 0x12345678 (81 E3 78 56 34 12) - ModR/M byte E3 = 11 100 011 (mod=3, reg=4, rm=3)
+        // mod=3 means direct register addressing, reg=4 indicates AND operation, rm=3 is EBX
+        byte[] codeBuffer = new byte[] { 0x81, 0xE3, 0x78, 0x56, 0x34, 0x12 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("and", instruction.Mnemonic);
+        Assert.Equal("ebx, 0x12345678", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the AndImmWithRm32SignExtendedHandler for decoding AND r/m32, imm8 instruction (sign-extended)
+    /// </summary>
+    [Fact]
+    public void AndImmWithRm32SignExtendedHandler_DecodesAndRm32Imm8_Correctly()
+    {
+        // Arrange
+        // AND EBX, 0x42 (83 E3 42) - ModR/M byte E3 = 11 100 011 (mod=3, reg=4, rm=3)
+        // mod=3 means direct register addressing, reg=4 indicates AND operation, rm=3 is EBX
+        // The immediate value 0x42 is sign-extended to 32 bits
+        byte[] codeBuffer = new byte[] { 0x83, 0xE3, 0x42 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("and", instruction.Mnemonic);
+        Assert.Equal("ebx, 0x00000042", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the XorImmWithRm32Handler for decoding XOR r/m32, imm32 instruction
+    /// </summary>
+    [Fact]
+    public void XorImmWithRm32Handler_DecodesXorRm32Imm32_Correctly()
+    {
+        // Arrange
+        // XOR ESI, 0x12345678 (81 F6 78 56 34 12) - ModR/M byte F6 = 11 110 110 (mod=3, reg=6, rm=6)
+        // mod=3 means direct register addressing, reg=6 indicates XOR operation, rm=6 is ESI
+        byte[] codeBuffer = new byte[] { 0x81, 0xF6, 0x78, 0x56, 0x34, 0x12 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("xor", instruction.Mnemonic);
+        Assert.Equal("esi, 0x12345678", instruction.Operands);
+    }
+    
+    /// <summary>
+    /// Tests the XorImmWithRm32SignExtendedHandler for decoding XOR r/m32, imm8 instruction (sign-extended)
+    /// </summary>
+    [Fact]
+    public void XorImmWithRm32SignExtendedHandler_DecodesXorRm32Imm8_Correctly()
+    {
+        // Arrange
+        // XOR ESI, 0x42 (83 F6 42) - ModR/M byte F6 = 11 110 110 (mod=3, reg=6, rm=6)
+        // mod=3 means direct register addressing, reg=6 indicates XOR operation, rm=6 is ESI
+        // The immediate value 0x42 is sign-extended to 32 bits
+        byte[] codeBuffer = new byte[] { 0x83, 0xF6, 0x42 };
+        var decoder = new InstructionDecoder(codeBuffer, codeBuffer.Length);
+        
+        // Act
+        var instruction = decoder.DecodeInstruction();
+        
+        // Assert
+        Assert.NotNull(instruction);
+        Assert.Equal("xor", instruction.Mnemonic);
+        Assert.Equal("esi, 0x00000042", instruction.Operands);
+    }
 }