Nine patients were described with a syndrome consisting of accommodative and convergence insufficiency. All but two had received extensive orthoptic therapy without benefit in the past. Near points of convergence and accommodation, fusional amplitudes and the AC/A ratio were determined and the data compared with those from a group with ordinary convergence insufficiency. The results show that this syndrome is a distinct and separate entity from ordinary convergence insufficiency. Special therapeutic measures include base in prisms and bifocal correction.