The author surveys the status of and issues surrounding year-round programs in secondary schools in order to provide background for deciding which school calendar is the most effective educationally, financially, and socially. The best programs and those discontinued are listed, as are the dates of the most important developments in year-round schooling. The current status of year-round programs is shown from data drawn both from California and nationwide. A series of tables also shows the public, curricular, and instructional issues most affected in schools that operate year-round. Along with summaries of the most vexing problems reported by experimental year-round programs, the report enumerates a range of functional problems, including those in the areas of curriculum and instruction, finance, scheduling of students, allocation of personnel, facilities and maintenance, transportation, school lunches, student activities and athletics, and support services. The paper also lists some advantages and points out the most promising programs. (JW)