“…We do not have space at this point for such a review. But suffice it to say that, despite some claims that diversity undermines the formation of a shared social identity and therefore makes groups less cohesive, less harmonious, less productive, and leaves members less satisfied (for a review, see van Knippenberg & Schippers, ), there is growing acceptance that (1) there is no simple and general relationship between diversity (including diversity due to immigration) and cohesion (Hickman, Crowley, & Mai, ; Saggar, Somerville, Ford, & Sobolewska, ), and that (2) in some circumstances diversity can increase group identification and cohesion, especially when it is consonant with group norms (van Knieppenberg, Haslam, & Platow, ; Visintin, Green, & Sarrasin, ). Clearly, though, the question of when diversity is or isn’t a problem for identification and cohesion is one that requires further clarification, and we have a responsibility not only to conduct the relevant research but also to inject the public debate so as to contest the simplifications and distortions that currently characterize that debate.…”