diff --git a/Core/ExpressionEvaluator.cpp b/Core/ExpressionEvaluator.cpp
index c202dd7b..d730f8a0 100644
--- a/Core/ExpressionEvaluator.cpp
+++ b/Core/ExpressionEvaluator.cpp
@@ -292,7 +292,7 @@ bool ExpressionEvaluator::ToRpn(string expression, ExpressionData &data)
 			if(!ProcessSpecialOperator(EvalOperators::Parenthesis, opStack, precedenceStack, data.RpnQueue)) {
 				return false;
 			}
-			operatorExpected = true;
+			operatorOrEndTokenExpected = true;
 		} else if(token[0] == '[') {
 			bracketCount++;
 			opStack.push(EvalOperators::Bracket);
@@ -302,7 +302,7 @@ bool ExpressionEvaluator::ToRpn(string expression, ExpressionData &data)
 			if(!ProcessSpecialOperator(EvalOperators::Bracket, opStack, precedenceStack, data.RpnQueue)) {
 				return false;
 			}
-			operatorExpected = true;
+			operatorOrEndTokenExpected = true;
 		} else if(token[0] == '{') {
 			braceCount++;
 			opStack.push(EvalOperators::Braces);
@@ -312,7 +312,7 @@ bool ExpressionEvaluator::ToRpn(string expression, ExpressionData &data)
 			if(!ProcessSpecialOperator(EvalOperators::Braces, opStack, precedenceStack, data.RpnQueue)){
 				return false;
 			}
-			operatorExpected = true;
+			operatorOrEndTokenExpected = true;
 		} else {
 			if(token[0] < '0' || token[0] > '9') {
 				return false;
@@ -605,5 +605,8 @@ void ExpressionEvaluator::RunTests()
 	test(":($1FFF+1)", EvalResultType::Numeric, -1);
 	test(":$1FFF+1", EvalResultType::Numeric, 0x800);
 	test("1+:$100", EvalResultType::Numeric, 0x101);
+
+	test("[$4100+[$4100]]", EvalResultType::Numeric, 0x41);
+	test("-($10+[$4100])", EvalResultType::Numeric, -0x51);
 }
 #endif
\ No newline at end of file
diff --git a/GUI.NET/Debugger/BreakpointManager.cs b/GUI.NET/Debugger/BreakpointManager.cs
index ca9b8d12..ad8aef66 100644
--- a/GUI.NET/Debugger/BreakpointManager.cs
+++ b/GUI.NET/Debugger/BreakpointManager.cs
@@ -22,6 +22,15 @@ namespace Mesen.GUI.Debugger
 			}
 		}
 
+		public static List<Breakpoint> Asserts { internal get; set; } = new List<Breakpoint>();
+
+		public static List<Breakpoint> GetAllBreakpoints()
+		{
+			List<Breakpoint> breakpoints = new List<Breakpoint>(BreakpointManager.Breakpoints);
+			breakpoints.AddRange(BreakpointManager.Asserts);
+			return breakpoints;
+		}
+
 		public static void RefreshBreakpoints(Breakpoint bp = null)
 		{
 			if(BreakpointsChanged != null) {
@@ -124,8 +133,15 @@ namespace Mesen.GUI.Debugger
 		public static void SetBreakpoints()
 		{
 			List<InteropBreakpoint> breakpoints = new List<InteropBreakpoint>();
-			for(int i = 0; i < Breakpoints.Count; i++) {
-				breakpoints.Add(Breakpoints[i].ToInteropBreakpoint(i));
+
+			ReadOnlyCollection<Breakpoint> userBreakpoints = BreakpointManager.Breakpoints;
+			for(int i = 0; i < userBreakpoints.Count; i++) {
+				breakpoints.Add(userBreakpoints[i].ToInteropBreakpoint(breakpoints.Count));
+			}
+
+			List<Breakpoint> assertBreakpoints = BreakpointManager.Asserts;
+			for(int i = 0; i < assertBreakpoints.Count; i++) {
+				breakpoints.Add(assertBreakpoints[i].ToInteropBreakpoint(breakpoints.Count));
 			}
 			InteropEmu.DebugSetBreakpoints(breakpoints.ToArray(), (UInt32)breakpoints.Count);
 		}
diff --git a/GUI.NET/Debugger/DbgImporter.cs b/GUI.NET/Debugger/DbgImporter.cs
index 7474729a..52c7248e 100644
--- a/GUI.NET/Debugger/DbgImporter.cs
+++ b/GUI.NET/Debugger/DbgImporter.cs
@@ -410,7 +410,7 @@ namespace Mesen.GUI.Debugger
 				_scopes.Add(scope.ID, scope);
 				return true;
 			} else if(row.StartsWith("scope")) {
-				System.Diagnostics.Debug.Fail("Regex doesn't match scope");
+				//System.Diagnostics.Debug.Fail("Regex doesn't match scope");
 			}
 
 			return false;
@@ -559,8 +559,12 @@ namespace Mesen.GUI.Debugger
 			}
 		}
 
+		private string[] _splitOnNewLine = { Environment.NewLine };
+
 		private void LoadComments()
 		{
+			SortedDictionary<string, int> constants = GetConstants();
+
 			foreach(KeyValuePair<int, LineInfo> kvp in _lines) {
 				try {
 					LineInfo line = kvp.Value;
@@ -622,7 +626,18 @@ namespace Mesen.GUI.Debugger
 						if(address >= 0 && addressType != null) {
 							CodeLabel label = this.CreateLabel(address, addressType.Value, 1);
 							if(label != null) {
-								label.Comment = comment;
+								//Parse and replace content of asserts as needed
+								string[] commentLines = comment.Split(_splitOnNewLine, StringSplitOptions.None);
+								for(int i = 0; i < commentLines.Length; i++) {
+									Match m = LabelManager.AssertRegex.Match(commentLines[i]);
+									if(m.Success) {
+										foreach(KeyValuePair<string, int> entry in constants) {
+											commentLines[i] = commentLines[i].Replace(entry.Key, entry.Value.ToString());
+										}
+									}
+								}
+
+								label.Comment = string.Join(Environment.NewLine, commentLines);
 							}
 						}
 					}
@@ -632,6 +647,26 @@ namespace Mesen.GUI.Debugger
 			}
 		}
 
+		private SortedDictionary<string, int> GetConstants()
+		{
+			SortedDictionary<string, int> constants = new SortedDictionary<string, int>(Comparer<string>.Create((string a, string b) => {
+				if(a.Length == b.Length) {
+					return a.CompareTo(b);
+				}
+				return b.Length - a.Length;
+			}));
+
+			foreach(Ld65DbgImporter.SymbolInfo symbol in GetSymbols()) {
+				AddressTypeInfo addressInfo = GetSymbolAddressInfo(symbol);
+				bool isConstant = addressInfo == null;
+				if(isConstant && symbol.Address.HasValue) {
+					constants[symbol.Name] = symbol.Address.Value;
+				}
+			}
+
+			return constants;
+		}
+
 		private void LoadFileData(string path)
 		{
 			Dictionary<int, int> maxLineCountByFile = new Dictionary<int, int>();
diff --git a/GUI.NET/Debugger/LabelManager.cs b/GUI.NET/Debugger/LabelManager.cs
index 831db51f..aaab7f0a 100644
--- a/GUI.NET/Debugger/LabelManager.cs
+++ b/GUI.NET/Debugger/LabelManager.cs
@@ -55,6 +55,7 @@ namespace Mesen.GUI.Debugger
 	public class LabelManager
 	{
 		public static Regex LabelRegex { get; } = new Regex("^[@_a-zA-Z]+[@_a-zA-Z0-9]*$", RegexOptions.Compiled);
+		public static Regex AssertRegex { get; } = new Regex(@"assert\((.*)\)", RegexOptions.Compiled);
 
 		private static Dictionary<UInt32, CodeLabel> _labelsByKey = new Dictionary<UInt32, CodeLabel>();
 		private static HashSet<CodeLabel> _labels = new HashSet<CodeLabel>();
@@ -98,10 +99,37 @@ namespace Mesen.GUI.Debugger
 				SetLabel(label.Address, label.AddressType, label.Label, label.Comment, false, label.Flags, label.Length);
 			}
 			if(raiseEvents) {
-				OnLabelUpdated?.Invoke(null, null);
+				ProcessLabelUpdate();
 			}
 		}
 
+		private static void ProcessLabelUpdate()
+		{
+			OnLabelUpdated?.Invoke(null, null);
+			UpdateAssertBreakpoints();
+		}
+
+		private static void UpdateAssertBreakpoints()
+		{
+			List<Breakpoint> asserts = new List<Breakpoint>();
+			foreach(CodeLabel label in LabelManager.GetLabels()) {
+				foreach(string commentLine in label.Comment.Split('\n')) {
+					Match m = LabelManager.AssertRegex.Match(commentLine);
+					if(m.Success) {
+						asserts.Add(new Breakpoint() {
+							BreakOnExec = true,
+							MemoryType = label.AddressType.ToMemoryType(),
+							Address = label.Address,
+							Condition = "!(" + m.Groups[1].Value + ")"
+						});
+					}
+				}
+			}
+
+			BreakpointManager.Asserts = asserts;
+			BreakpointManager.SetBreakpoints();
+		}
+
 		public static List<CodeLabel> GetLabels()
 		{
 			return _labels.ToList<CodeLabel>();
@@ -154,7 +182,7 @@ namespace Mesen.GUI.Debugger
 			}
 
 			if(raiseEvent) {
-				OnLabelUpdated?.Invoke(null, null);
+				ProcessLabelUpdate();
 			}
 
 			return true;
@@ -180,7 +208,7 @@ namespace Mesen.GUI.Debugger
 			}
 
 			if(needEvent) {
-				OnLabelUpdated?.Invoke(null, null);
+				ProcessLabelUpdate();
 			}
 		}
 
diff --git a/GUI.NET/Debugger/frmDebugger.cs b/GUI.NET/Debugger/frmDebugger.cs
index 3aec9950..a02d5980 100644
--- a/GUI.NET/Debugger/frmDebugger.cs
+++ b/GUI.NET/Debugger/frmDebugger.cs
@@ -451,19 +451,24 @@ namespace Mesen.GUI.Debugger
 					BreakpointType bpType = (BreakpointType)(byte)((param >> 8) & 0x0F);
 					UInt16 bpAddress = (UInt16)(param >> 16);
 
-					ReadOnlyCollection<Breakpoint> breakpoints = BreakpointManager.Breakpoints;
+					int regularBpCount = BreakpointManager.Breakpoints.Count;
+					List<Breakpoint> breakpoints = BreakpointManager.GetAllBreakpoints();
 					if(breakpointId >= 0 && breakpointId < breakpoints.Count) {
 						Breakpoint bp = breakpoints[breakpointId];
-						if(bpType != BreakpointType.Global) {
-							message += ": " + ResourceHelper.GetEnumText(bpType) + " ($" + bpAddress.ToString("X4") + ":$" + bpValue.ToString("X2") + ")";
-						}
-						if(!string.IsNullOrWhiteSpace(bp.Condition)) {
-							string cond = bp.Condition.Trim();
-							if(cond.Length > 27) {
-								message += Environment.NewLine + cond.Substring(0, 24) + "...";
-							} else {
-								message += Environment.NewLine + cond;
+						if(breakpointId < regularBpCount) {
+							if(bpType != BreakpointType.Global) {
+								message += ": " + ResourceHelper.GetEnumText(bpType) + " ($" + bpAddress.ToString("X4") + ":$" + bpValue.ToString("X2") + ")";
 							}
+							if(!string.IsNullOrWhiteSpace(bp.Condition)) {
+								string cond = bp.Condition.Trim();
+								if(cond.Length > 27) {
+									message += Environment.NewLine + cond.Substring(0, 24) + "...";
+								} else {
+									message += Environment.NewLine + cond;
+								}
+							}
+						} else {
+							message = "Assert failed: " + bp.Condition.Substring(2, bp.Condition.Length - 3);
 						}
 					}
 				} else if(source == BreakSource.BreakOnUninitMemoryRead) {