This study evaluated the effectiveness of the Gang Prevention Through Targeted Outreach (GPTTO) and Gang Intervention Through Targeted Outreach (GITTO) initiatives of the Boys & Girls Clubs of America. The study examined whether the clubs were attracting youth at high risk of gang involvement, whether clubs could keep GPTTO and GITTO youth participating in the club or program, whether GITTO and GPTTO youth were receiving positive supports through participation in the club, and whether participation had positive effects on the lives of GPTTO and GITTO youth. The evaluation involved 21 clubs that used the prevention approach and 3 that used the intervention approach. Survey results indicated that GPTTO and GITTO were meeting their goals. Clubs attracted and retained youth at high risk of gang involvement. GPTTO and GITTO youth received key developmental supports at the clubs that they might otherwise seek through involvement with gangs. Those who participated more frequently experienced positive outcomes. The estimated incremental cost per youth per year of the GPTTO and GITTO approaches were far less than the cost of gang suppression. Four appendices include sample sites; survey sample at baseline and follow-up; construct list with items, response categories, and reliability coefficients; and analytic strategies. (Contains 38 references.) (SM)