Hi, It's in the Erlang documentation. Has this been removed (tried on R15B01 and R15B03)? Erlang R15B01 (erts-5.9.1) [source] [smp:8:8] [async-threads:0] [hipe] [kernel-poll:false] Eshell V5.9.1 (abort with ^G) 1> erlang:delete_element(2, {one, two, three}). ** exception error: undefined function erlang:delete_element/2 2>