The Authority should consult interested parties on regulatory or implementing technical standards, guidelines and recommendations and provide them with a reasonable opportunity to comment on proposed measures. Before adopting draft regulatory or implementing technical standards, guidelines and recommendations, the Authority should carry out an impact study. For reasons of efficiency, a Banking Stakeholder Group should be used for that purpose, and should represent, in balanced proportions, Union credit and investment institutions, representing the diverse models and sizes of financial institutions and businesses, including, as appropriate, institutional investors and other financial institutions which themselves use financial services; small and medium-sized enterprises (SMEs); trade unions; academics; consumers; and other retail users of banking services. The Banking Stakeholder Group should work as an interface with other user groups in the financial services area established by the Commission or by Union legislation.