Justin-Siena High School is a Roman Catholic college preparatory school in the Lasallian tradition, located in Napa, California within the Roman Catholic Diocese of Santa Rosa in California. The school was created when Justin High School for males, sponsored by the Christian Brothers of the San Francisco District, merged with St. Catherine of Siena High School for females, sponsored by the Dominican Sisters of San Rafael in 1972. The student population currently numbers approximately 670. It provides education to a diverse student population including North Bay residents from Napa, Solano, and Sonoma Counties, as well as international students. Justin-Siena has awarded more than $1.54 million in tuition assistance for the 2013-14 school year. Approximately 32.87% of students receive tuition assistance with the average grant covering 48.6% of tuition.