The role played by social relationship variables (attachment security; mother-child relationship qualities) and social-cognitive capacities (theory of mind) was examined in both observed friendship behaviors and in children's descriptions of friendships (age 8-12) with high functioning children with autism spectrum disorders (HFASD) (n = 44) and with typical development (TYP) (n = 38). Overall, half of the HFASD sample (54.45%) reported maternal attachment security, corroborating data from younger children with ASD. The hypothesized predictors and their interrelations had both direct and indirect effects on friendship for both groups of children, highlighting the importance of these factors in children's friendship development and suggesting both compensatory and amplification mechanisms for friendship qualities. Practical and clinical implications are discussed for friendship support in both ASD and TYP. (Contains 4 tables.)