▁in ▁the ▁program ▁actually ▁exists ▁in ▁the ▁population ; ▁whether ▁it ▁is , ▁in ▁fact , ▁a ▁problem ; ▁and ▁if ▁so , ▁how ▁it ▁might ▁best ▁be ▁de alt ▁with . ▁This ▁includes ▁ident ifying ▁and ▁diagn osing ▁the ▁actual ▁problem ▁the ▁program ▁is ▁trying ▁to ▁address , ▁who ▁or ▁what ▁is ▁affected ▁by ▁the ▁problem , ▁how ▁w ides p read ▁the ▁problem ▁is , ▁and ▁what ▁are ▁the ▁meas urable ▁effects ▁that ▁are ▁caused ▁by ▁the ▁problem . ▁For ▁example , ▁for ▁a ▁housing ▁program ▁aim ed ▁at ▁mit ig ating ▁hom eless ness , ▁a ▁program ▁evalu ator ▁may ▁want ▁to ▁find ▁out ▁how ▁many ▁people ▁are ▁hom eless ▁in ▁a ▁given ▁ge ographic ▁area ▁and ▁what ▁their ▁dem ograph ics ▁are . ▁Ros si , ▁Lip sey ▁and ▁Fre eman ▁( 2 0 0 4 ) ▁ca ution ▁against ▁undert aking ▁an ▁inter vention ▁without ▁properly ▁assess ing ▁the ▁need ▁for ▁one , ▁because ▁this ▁might ▁result ▁in ▁a ▁great ▁deal ▁of ▁was ted ▁funds ▁if ▁the ▁need ▁did ▁not ▁exist ▁or ▁was ▁mis con ce ived . ▁ ▁Ne eds ▁assess ment ▁involves ▁the ▁processes ▁or ▁methods ▁used ▁by ▁evalu ators ▁to ▁describe ▁and ▁diagn ose ▁social ▁needs ▁This ▁is ▁essential ▁for ▁evalu ators ▁because ▁they ▁need ▁to ▁identify ▁whether ▁programs ▁are ▁effective ▁and ▁they ▁cannot ▁do ▁this ▁unless ▁they ▁have ▁identified ▁what ▁the ▁problem / need ▁is . ▁Program s ▁that ▁do ▁not ▁do ▁a ▁needs ▁assess ment ▁can ▁have ▁the ▁ill usion ▁that ▁they ▁have