The number of online search services commercially available to the public today has, in many cases, complicated the search process for the casual user. Faced with an increasing number of systems, each one necessitating the mastery of a different retrieval language and a particular set of protocols, the user is left confused and often unable to satisfactorily complete his search. This study compares the syntax, semantics and functions of the different languages used by some of the commercial IS&R systems available in the United States today. It also leads to a proposal for a common command language which would cover the functions most needed during the retrieval process.