A multiple probe study across behaviors, replicated across participants, assessed effectiveness of peer delivered simultaneous prompting (SP) in teaching expressively identifying community signs to four students with developmental disabilities. The two purposes of the study were: (a) to find out if Peer tutors use simultaneous Prompting reliably for instructing their tutees with developmental disabilities, and (b) to examine effectiveness of simultaneous prompting on teaching expressively identifying community signs. The definition of community sign was presented as instructive feedback. Besides these aims, generalization and maintenance effects of simultaneous prompting were also investigated in the study. Generalization across Persons was tested before introducing simultaneous prompting and after tutees met criteria. Maintenance data for targeted and non-targeted behaviors were collected one week after instruction. Results show that peer tutors deliver SP reliably, and tutees acquired expressively identifying community signs. Tutees also gained some instructive feedback. Furthermore, tutees maintained acquired skills at criterion level and generalized acquired skills to another person at criterion level. Based upon evaluation of findings and implications of the study future research needs are discussed.