Abstract: This invention relates to a support assembly for supporting a control device such as a keyboard relative to a fixed support such as a bench or table which may support visual display apparatus. The support assembly includes support means such as a table top or desk top for supporting the control device and attachment means such as an attachment bracket for attachment of the support assembly to the fixed support.There is also included linkage means pivotally interconnecting each of the support means and attachment means. In the preferred form the linkage means includes an upper linkage arm and lower auxiliary support member forming a parallelogram linkage. There is also included fluid operated means for actuating movement of the linkage means whereby the support means may move in a direction spaced from the fixed support.