diff --git a/src/protocol/ast.rs b/src/protocol/ast.rs
index 95195aef473b46c535fb2b034a712da10bf953ca..a8b18a801eef40f745879bd48630af59c8159dc3 100644
--- a/src/protocol/ast.rs
+++ b/src/protocol/ast.rs
@@ -137,6 +137,8 @@ define_new_ast_id!(SynchronousStatementId, StatementId, index(SynchronousStateme
 define_new_ast_id!(EndSynchronousStatementId, StatementId, index(EndSynchronousStatement, Statement::EndSynchronous, statements), alloc(alloc_end_synchronous_statement));
 define_new_ast_id!(ForkStatementId, StatementId, index(ForkStatement, Statement::Fork, statements), alloc(alloc_fork_statement));
 define_new_ast_id!(EndForkStatementId, StatementId, index(EndForkStatement, Statement::EndFork, statements), alloc(alloc_end_fork_statement));
+define_new_ast_id!(SelectStatementId, StatementId, index(SelectStatement, Statement::Select, statements), alloc(alloc_select_statement));
+define_new_ast_id!(EndSelectStatementId, StatementId, index(EndSelectStatement, Statement::EndSelect, statements), alloc(alloc_end_select_statement));
 define_new_ast_id!(ReturnStatementId, StatementId, index(ReturnStatement, Statement::Return, statements), alloc(alloc_return_statement));
 define_new_ast_id!(GotoStatementId, StatementId, index(GotoStatement, Statement::Goto, statements), alloc(alloc_goto_statement));
 define_new_ast_id!(NewStatementId, StatementId, index(NewStatement, Statement::New, statements), alloc(alloc_new_statement));
@@ -1068,6 +1070,8 @@ pub enum Statement {
     EndSynchronous(EndSynchronousStatement),
     Fork(ForkStatement),
     EndFork(EndForkStatement),
+    Select(SelectStatement),
+    EndSelect(EndSelectStatement),
     Return(ReturnStatement),
     Goto(GotoStatement),
     New(NewStatement),
@@ -1112,11 +1116,17 @@ impl Statement {
             Statement::Continue(v) => v.span,
             Statement::Synchronous(v) => v.span,
             Statement::Fork(v) => v.span,
+            Statement::Select(v) => v.span,
             Statement::Return(v) => v.span,
             Statement::Goto(v) => v.span,
             Statement::New(v) => v.span,
             Statement::Expression(v) => v.span,
-            Statement::EndBlock(_) | Statement::EndIf(_) | Statement::EndWhile(_) | Statement::EndSynchronous(_) | Statement::EndFork(_) => unreachable!(),
+            Statement::EndBlock(_)
+            | Statement::EndIf(_)
+            | Statement::EndWhile(_)
+            | Statement::EndSynchronous(_)
+            | Statement::EndFork(_)
+            | Statement::EndSelect(_) => unreachable!(),
         }
     }
     pub fn link_next(&mut self, next: StatementId) {
@@ -1131,6 +1141,7 @@ impl Statement {
             Statement::EndWhile(stmt) => stmt.next = next,
             Statement::EndSynchronous(stmt) => stmt.next = next,
             Statement::EndFork(stmt) => stmt.next = next,
+            Statement::EndSelect(stmt) => stmt.next = next,
             Statement::New(stmt) => stmt.next = next,
             Statement::Expression(stmt) => stmt.next = next,
             Statement::Return(_)
@@ -1138,6 +1149,7 @@ impl Statement {
             | Statement::Continue(_)
             | Statement::Synchronous(_)
             | Statement::Fork(_)
+            | Statement::Select(_)
             | Statement::Goto(_)
             | Statement::While(_)
             | Statement::Labeled(_)
@@ -1335,6 +1347,28 @@ pub struct EndForkStatement {
     pub next: StatementId,
 }
 
+#[derive(Debug, Clone)]
+pub struct SelectStatement {
+    pub this: SelectStatementId,
+    pub span: InputSpan, // of the "select" keyword
+    pub cases: Vec<SelectCase>,
+    pub end_select: EndSelectStatementId,
+}
+
+#[derive(Debug, Clone)]
+pub struct SelectCase {
+    pub guard_var: Option<MemoryStatementId>, // optional memory declaration
+    pub guard_expr: ExpressionStatementId, // if `guard_var.is_some()`, then always assignment expression
+    pub block: BlockStatementId,
+}
+
+#[derive(Debug, Clone)]
+pub struct EndSelectStatement {
+    pub this: EndSelectStatementId,
+    pub start_select: SelectStatementId,
+    pub next: StatementId,
+}
+
 #[derive(Debug, Clone)]
 pub struct ReturnStatement {
     pub this: ReturnStatementId,