diff --git a/grammars/csharp.tmLanguage b/grammars/csharp.tmLanguage
index 6b6a385..633efa1 100644
--- a/grammars/csharp.tmLanguage
+++ b/grammars/csharp.tmLanguage
@@ -660,7 +660,7 @@
       <key>attribute-section</key>
       <dict>
         <key>begin</key>
-        <string>(\[)(assembly|module|field|event|method|param|property|return|type)?(\:)?</string>
+        <string>(\[)(assembly|module|event|field|method|param|property|return|type|typevar)?(\:)?</string>
         <key>beginCaptures</key>
         <dict>
           <key>1</key>
@@ -2725,12 +2725,38 @@
             <key>include</key>
             <string>#ref-modifier</string>
           </dict>
+          <dict>
+            <key>include</key>
+            <string>#lambda-expression</string>
+          </dict>
           <dict>
             <key>include</key>
             <string>#expression</string>
           </dict>
         </array>
       </dict>
+      <key>lambda-expression</key>
+      <dict>
+        <key>begin</key>
+        <string>(?=(?:\[.*\].*)?\(.*\).*=&gt;)</string>
+        <key>end</key>
+        <string>(?=;)</string>
+        <key>patterns</key>
+        <array>
+          <dict>
+            <key>include</key>
+            <string>#attribute-section</string>
+          </dict>
+          <dict>
+            <key>include</key>
+            <string>#parenthesized-parameter-list</string>
+          </dict>
+          <dict>
+            <key>include</key>
+            <string>#expression-body</string>
+          </dict>
+        </array>
+      </dict>
       <key>expression-body</key>
       <dict>
         <key>begin</key>
@@ -7270,6 +7296,10 @@
             <key>include</key>
             <string>#parameter</string>
           </dict>
+          <dict>
+            <key>include</key>
+            <string>#parameter-identifier</string>
+          </dict>
           <dict>
             <key>include</key>
             <string>#punctuation-comma</string>
@@ -7333,6 +7363,13 @@
           </dict>
         </dict>
       </dict>
+      <key>parameter-identifier</key>
+      <dict>
+        <key>name</key>
+        <string>entity.name.variable.parameter.cs</string>
+        <key>match</key>
+        <string>(?&lt;!\.)@?\b[_[:alpha:]][_[:alnum:]]*\b(?!\.)</string>
+      </dict>
       <key>argument-list</key>
       <dict>
         <key>begin</key>
diff --git a/grammars/csharp.tmLanguage.cson b/grammars/csharp.tmLanguage.cson
index 3f09e3e..c3252c7 100644
--- a/grammars/csharp.tmLanguage.cson
+++ b/grammars/csharp.tmLanguage.cson
@@ -441,7 +441,7 @@ repository:
       }
     ]
   "attribute-section":
-    begin: "(\\[)(assembly|module|field|event|method|param|property|return|type)?(\\:)?"
+    begin: "(\\[)(assembly|module|event|field|method|param|property|return|type|typevar)?(\\:)?"
     beginCaptures:
       "1":
         name: "punctuation.squarebracket.open.cs"
@@ -1738,10 +1738,27 @@ repository:
       {
         include: "#ref-modifier"
       }
+      {
+        include: "#lambda-expression"
+      }
       {
         include: "#expression"
       }
     ]
+  "lambda-expression":
+    begin: "(?=(?:\\[.*\\].*)?\\(.*\\).*=>)"
+    end: "(?=;)"
+    patterns: [
+      {
+        include: "#attribute-section"
+      }
+      {
+        include: "#parenthesized-parameter-list"
+      }
+      {
+        include: "#expression-body"
+      }
+    ]
   "expression-body":
     begin: "=>"
     beginCaptures:
@@ -4383,6 +4400,9 @@ repository:
       {
         include: "#parameter"
       }
+      {
+        include: "#parameter-identifier"
+      }
       {
         include: "#punctuation-comma"
       }
@@ -4430,6 +4450,9 @@ repository:
         ]
       "7":
         name: "entity.name.variable.parameter.cs"
+  "parameter-identifier":
+    name: "entity.name.variable.parameter.cs"
+    match: "(?<!\\.)@?\\b[_[:alpha:]][_[:alnum:]]*\\b(?!\\.)"
   "argument-list":
     begin: "\\("
     beginCaptures:
diff --git a/src/csharp.tmLanguage.yml b/src/csharp.tmLanguage.yml
index 360b7d2..bbf4b37 100644
--- a/src/csharp.tmLanguage.yml
+++ b/src/csharp.tmLanguage.yml
@@ -187,7 +187,7 @@ repository:
       - include: '#operator-assignment'
 
   attribute-section:
-    begin: (\[)(assembly|module|field|event|method|param|property|return|type)?(\:)?
+    begin: (\[)(assembly|module|event|field|method|param|property|return|type|typevar)?(\:)?
     beginCaptures:
       '1': { name: punctuation.squarebracket.open.cs }
       '2': { name: keyword.other.attribute-specifier.cs }
@@ -1024,8 +1024,17 @@ repository:
     end: (?=[,\)\];}])
     patterns:
     - include: '#ref-modifier'
+    - include: '#lambda-expression'
     - include: '#expression'
 
+  lambda-expression:
+    begin: (?=(?:\[.*\].*)?\(.*\).*=>)
+    end: (?=;)
+    patterns:
+    - include: '#attribute-section'
+    - include: '#parenthesized-parameter-list'
+    - include: '#expression-body'
+
   expression-body:
     begin: =>
     beginCaptures:
@@ -2823,6 +2832,7 @@ repository:
     - include: '#comment'
     - include: '#attribute-section'
     - include: '#parameter'
+    - include: '#lambda-parameter'
     - include: '#punctuation-comma'
     - include: '#variable-initializer'
 
@@ -2865,6 +2875,10 @@ repository:
       # '6': ?<tuple> is a sub-expression. It's final value is not considered.
       7: { name: entity.name.variable.parameter.cs }
 
+  lambda-parameter:
+    name: entity.name.variable.parameter.cs
+    match: '(?<!\.)@?\b[_[:alpha:]][_[:alnum:]]*\b(?!\.)'
+
   argument-list:
     begin: \(
     beginCaptures:
diff --git a/test/expressions.tests.ts b/test/expressions.tests.ts
index 95dd1bb..24e8c8e 100644
--- a/test/expressions.tests.ts
+++ b/test/expressions.tests.ts
@@ -435,6 +435,103 @@ var a = new A // comment
         ]);
       });
 
+      it("lambda with attributes (issue #303)", async () => {
+        const input = Input.InMethod(`
+var concat = ([DisallowNull] string a, [DisallowNull] string b) => a + b;
+var inc = [return: NotNullIfNotNull(nameof(s))] (int? s) => s.HasValue ? s++ : null;
+Func<string?, int?> parse = [ProvidesNullCheck] (s) => (s is not null) ? int.Parse(s) : null;
+`);
+        const tokens = await tokenize(input);
+
+        tokens.should.deep.equal([
+          Token.Keyword.Definition.Var,
+          Token.Identifier.LocalName("concat"),
+          Token.Operator.Assignment,
+          Token.Punctuation.OpenParen,
+          Token.Punctuation.OpenBracket,
+          Token.Type("DisallowNull"),
+          Token.Punctuation.CloseBracket,
+          Token.PrimitiveType.String,
+          Token.Identifier.ParameterName("a"),
+          Token.Punctuation.Comma,
+          Token.Punctuation.OpenBracket,
+          Token.Type("DisallowNull"),
+          Token.Punctuation.CloseBracket,
+          Token.PrimitiveType.String,
+          Token.Identifier.ParameterName("b"),
+          Token.Punctuation.CloseParen,
+          Token.Operator.Arrow,
+          Token.Variable.ReadWrite("a"),
+          Token.Operator.Arithmetic.Addition,
+          Token.Variable.ReadWrite("b"),
+          Token.Punctuation.Semicolon,
+
+          Token.Keyword.Definition.Var,
+          Token.Identifier.LocalName("inc"),
+          Token.Operator.Assignment,
+          Token.Punctuation.OpenBracket,
+          Token.Keyword.AttributeSpecifier("return"),
+          Token.Punctuation.Colon,
+          Token.Type("NotNullIfNotNull"),
+          Token.Punctuation.OpenParen,
+          Token.Operator.Expression.NameOf,
+          Token.Punctuation.OpenParen,
+          Token.Variable.ReadWrite("s"),
+          Token.Punctuation.CloseParen,
+          Token.Punctuation.CloseParen,
+          Token.Punctuation.CloseBracket,
+          Token.Punctuation.OpenParen,
+          Token.PrimitiveType.Int,
+          Token.Punctuation.QuestionMark,
+          Token.Identifier.ParameterName("s"),
+          Token.Punctuation.CloseParen,
+          Token.Operator.Arrow,
+          Token.Variable.Object("s"),
+          Token.Punctuation.Accessor,
+          Token.Variable.Property("HasValue"),
+          Token.Operator.Conditional.QuestionMark,
+          Token.Variable.ReadWrite("s"),
+          Token.Operator.Increment,
+          Token.Operator.Conditional.Colon,
+          Token.Literal.Null,
+          Token.Punctuation.Semicolon,
+
+          Token.Type("Func"),
+          Token.Punctuation.TypeParameter.Begin,
+          Token.PrimitiveType.String,
+          Token.Punctuation.QuestionMark,
+          Token.Punctuation.Comma,
+          Token.PrimitiveType.Int,
+          Token.Punctuation.QuestionMark,
+          Token.Punctuation.TypeParameter.End,
+          Token.Identifier.LocalName("parse"),
+          Token.Operator.Assignment,
+          Token.Punctuation.OpenBracket,
+          Token.Type("ProvidesNullCheck"),
+          Token.Punctuation.CloseBracket,
+          Token.Punctuation.OpenParen,
+          Token.Identifier.ParameterName("s"),
+          Token.Punctuation.CloseParen,
+          Token.Operator.Arrow,
+          Token.Punctuation.OpenParen,
+          Token.Variable.ReadWrite("s"),
+          Token.Operator.Pattern.Is,
+          Token.Operator.Pattern.Not,
+          Token.Literal.Null,
+          Token.Punctuation.CloseParen,
+          Token.Operator.Conditional.QuestionMark,
+          Token.PrimitiveType.Int,
+          Token.Punctuation.Accessor,
+          Token.Identifier.MethodName("Parse"),
+          Token.Punctuation.OpenParen,
+          Token.Variable.ReadWrite("s"),
+          Token.Punctuation.CloseParen,
+          Token.Operator.Conditional.Colon,
+          Token.Literal.Null,
+          Token.Punctuation.Semicolon
+        ]);
+      });
+
       it("async lambda assigned to dotted name (issue #142)", async () => {
         const input = Input.InMethod(
           `Something.listener = async args => { return true; };`