*Concise and practical: experts present skill units based on five core principles of change, giving providers maximum flexibility to tailor treatments to children's (ages 6 to 15) unique needs. *FIRST is an alternative to manuals that address a single problem, can be used with simple or complex cases, and is efficient to learn. *The treatment is empirically based but designed for real-world community practice; includes reproducible parent handouts in English and Spanish. *Each skill unit is effective used on its own, of key benefit for youths who may not stay in treatment long.