While the development of life skills (e.g., communication, problem solving, etc.) is a commonly targeted youth program outcome, the lack of standardized conceptualizations and instrumentation make it difficult to compare impacts across programs and develop validated best practices. In order to promote a more unified approach to life skill development, literature reviews were conducted for 10 life skill domains to identify common definitions and, if available, appropriate outcome measures. Data were then collected from an ethnically diverse sample (N = 758) of elementary, middle, and high school aged youth for the 10 identified instruments. Analyses were conducted to ascertain the psychometric qualities of each measure, the interrelationships among measures, and the measures’ relationships with gender, ethnicity, and school level. Results are discussed in terms of their relevance to life skill theory and measurement.