diff --git a/README.md b/README.md
index 059b853..ed92ebb 100644
--- a/README.md
+++ b/README.md
@@ -66,6 +66,14 @@ A simple query that operates on JSON logs and counts the number of logs per leve
 agrind '* | json | count by log_level'
 ```
 
+### Escaping Field Names
+
+Field names containing a space or period must be escaped using `["<FIELD>"]`:
+
+```bash
+agrind '* | json | count by ["date received"], ["grpc.method"]
+```
+
 ### Filters
 
 There are three basic filters:
diff --git a/src/lang.rs b/src/lang.rs
index fb2baf8..78946bb 100644
--- a/src/lang.rs
+++ b/src/lang.rs
@@ -366,6 +366,14 @@ fn is_ident(c: char) -> bool {
     is_alphanumeric(c as u8) || c == '_'
 }
 
+fn is_escaped_ident(c: char) -> bool {
+    match c {
+        space if is_space(space as u8) => true,
+        '.' => true,
+        _ => is_ident(c),
+    }
+}
+
 fn starts_ident(c: char) -> bool {
     is_alphabetic(c as u8) || c == '_'
 }
@@ -431,12 +439,20 @@ named!(column_ref<Span, Expr>, do_parse!(
     (Expr::Column { head: DataAccessAtom::Key(head), rest: rest })
 ));
 
-named!(ident<Span, String>, do_parse!(
+named!(ident<Span, String>, alt!(bare_ident | escaped_ident));
+
+named!(bare_ident<Span, String>, do_parse!(
     start: take_while1!(starts_ident) >>
     rest: take_while!(is_ident) >>
     (start.fragment.0.to_owned() + rest.fragment.0)
 ));
 
+named!(escaped_ident<Span, String>, do_parse!(
+    start: preceded!(tag!("[\""), take_while1!(starts_ident)) >>
+    rest: terminated!(take_while!(is_escaped_ident), tag!("\"]")) >>
+    (start.fragment.0.to_owned() + rest.fragment.0)
+));
+
 named!(arguments<Span, Vec<Expr>>, add_return_error!(SyntaxErrors::StartOfError.into(), delimited!(
    tag!("("),
    separated_list!(tag!(","), expr),
@@ -1166,6 +1182,13 @@ mod tests {
         expect_fail!(ident, "5x");
     }
 
+    #[test]
+    fn parse_quoted_ident() {
+        expect!(ident, "[\"hello world\"]", "hello world".to_string());
+        expect!(ident, "[\"hello.world\"]", "hello.world".to_string());
+        expect_fail!(ident, "\"\"");
+    }
+
     #[test]
     fn parse_var_list() {
         expect!(
diff --git a/tests/structured_tests/escaped_ident.toml b/tests/structured_tests/escaped_ident.toml
new file mode 100644
index 0000000..2af42a8
--- /dev/null
+++ b/tests/structured_tests/escaped_ident.toml
@@ -0,0 +1,13 @@
+query = """
+* | json | count by ["grpc.method"], ["start time"]
+"""
+input = """
+{"start time": "today", "grpc.method": "Foo"}
+{"start time": "today", "grpc.method": "Bar"}
+"""
+output = """
+["grpc.method"]        ["start time"]        _count
+-----------------------------------------------------------
+Bar                    today                 1
+Foo                    today                 1
+"""