▁club ▁meet ings , ▁sports ▁activities , ▁t utor ing , ▁individual ▁coun sel ing , ▁and ▁advoc acy ▁with ▁community ▁ag encies ▁and ▁organizations . ▁However , ▁Klein ▁claims ▁that ▁" in cre ased ▁group ▁programming ▁leads ▁to ▁increased ▁coh es iveness ▁( in ▁both ▁gang ▁growth ▁and ▁gang ▁' t ight ness '), ▁and ▁increased ▁coh es iveness ▁leads ▁to ▁increased ▁gang ▁crime ." ▁Klein ▁bel ieves ▁that ▁coh es ion ▁is ▁one ▁( if ▁not ▁the ▁biggest ) ▁part ▁of ▁a ▁street ▁gang ▁and ▁with ▁programs ▁like ▁these , ▁it ▁only ▁serves ▁to ▁increase ▁coh es ion ▁between ▁gang s ▁by ▁giving ▁them ▁a ▁more ▁organized ▁methods ▁towards ▁their ▁activities . ▁ ▁Klein ' s ▁research ▁also ▁expanded ▁to ▁an ▁international ▁level , ▁where ▁he ▁instit uted ▁" com par ative ▁cr imin ology ." ▁In ▁" com par ative ▁cr imin ology ," ▁Klein ▁exam ines ▁many ▁differences ▁and ▁similar ities ▁on ▁how ▁different ▁cult ures ▁affect ▁different ▁gang s ▁in ▁different ▁regions ▁of ▁the ▁world , ▁their ▁behavior al ▁reg ulations , ▁structures ▁and ▁organizations ▁of ▁gang s , ▁and ▁also ▁del in qu encies ▁and ▁cr imes ▁of ▁those ▁areas . ▁One ▁big ▁project ▁that ▁he ▁emb ark ed ▁on ▁for ▁this ▁global ▁research ▁on ▁gang s ▁was ▁the ▁Euro gang ▁Project ▁in ▁ 1 9 9 8 , ▁where ▁he ▁went ▁to ▁Sch mit ten , ▁Germany ▁for ▁a ▁conference ▁among ▁American ▁and ▁European ▁research ers ▁to ▁discuss ▁the ▁different ▁aspects ▁of ▁cr imin ology ▁that