diff --git a/openssl-sys/src/lib.rs b/openssl-sys/src/lib.rs
index a8ac9ba1..0ea0e5d8 100644
--- a/openssl-sys/src/lib.rs
+++ b/openssl-sys/src/lib.rs
@@ -1751,6 +1751,7 @@ extern {
     pub fn SSL_get_session(s: *const SSL) -> *mut SSL_SESSION;
 
     pub fn SSL_SESSION_free(s: *mut SSL_SESSION);
+    pub fn SSL_SESSION_get_id(s: *const SSL_SESSION, len: *mut c_uint) -> *const c_uchar;
 
     #[cfg(not(ossl101))]
     pub fn SSL_CTX_set_alpn_protos(s: *mut SSL_CTX, data: *const c_uchar, len: c_uint) -> c_int;
diff --git a/openssl/src/ssl/mod.rs b/openssl/src/ssl/mod.rs
index d1ed55fe..3949210d 100644
--- a/openssl/src/ssl/mod.rs
+++ b/openssl/src/ssl/mod.rs
@@ -1029,6 +1029,19 @@ impl SslCipherRef {
     }
 }
 
+type_!(SslSession, SslSessionRef, ffi::SSL_SESSION, ffi::SSL_SESSION_free);
+
+impl SslSessionRef {
+    /// Returns the SSL session ID.
+    pub fn id(&self) -> &[u8] {
+        unsafe {
+            let mut len = 0;
+            let p = ffi::SSL_SESSION_get_id(self.as_ptr(), &mut len);
+            slice::from_raw_parts(p as *const u8, len as usize)
+        }
+    }
+}
+
 type_!(Ssl, SslRef, ffi::SSL, ffi::SSL_free);
 
 impl fmt::Debug for SslRef {
@@ -1350,8 +1363,6 @@ impl fmt::Debug for Ssl {
     }
 }
 
-type_!(SslSession, SslSessionRef, ffi::SSL_SESSION, ffi::SSL_SESSION_free);
-
 impl Ssl {
     pub fn new(ctx: &SslContext) -> Result<Ssl, ErrorStack> {
         unsafe {