This dissertation examines the prevalence rates of students with disabilities in grades kindergarten through twelve in the 115 special education local plan areas (SELPAs) in the state of California. California moved to a new, population-based funding model in 1998, assuming that the prevalence of students with disabilities requiring special education is equitably distributed. Special education services and funds will flow through the agencies known as SELPAs based on 10% of the SELPAs' total student population. No prior study was undertaken to validate the assumption of equitable distribution of students with disabilities in California by their SELPA of residence. This study attempted to provide data and examine the prevalence of students identified as needing special education based on their SELPA of residence as a basis for accurate statewide policy development. This study examined the total number of special education students as well as the number of special education students in each of the 13 disabling categories as a percentage of the total student population in each of 115 SELPAs in California to determine if such students were equitably distributed. Descriptive statistics for each disability and the total number of special education students in the SELPAs are provided. This study also examined four factors of the SELPAs which contributed to differences in prevalence rates. These factors are: percentages of low-income students; percentages of limited-English proficient students; percentages of students from ethnic minorities; and geographic location (rural, suburban, urban). Data from this study showed that special education students as a percentage of the total seudent population are not equitably distributed; the distributions for each of the disabling categories are quite different; and the various characteristics ofthe SELPAs are correlated with the prevalence rates of the disabilities in a variety of ways.