Not AvailableThis article investigates the robustness aspects of binary variance balanced block designs against interchange of a pair of treatments in two blocks of the design using connectedness and relative efficiency criterion. The different classes of binary variance balanced block (VBD) designs viz. randomized complete block designs, balanced incomplete block designs, non-proper unequireplicated VBD’s of Kageyama (12) and non-proper equireplicated VBD’s of Gupta and Jones (7) have been found robust.Not Availabl