The purpose of the study was to identify in-service general and special educators', counselors', and English as a Second Language educators' perceptions of the cause of academic difficulties for students who are culturally and linguistically diverse (CLD). A mixed-methods sequential explanatory design was used to initially collect quantitative data though an online survey with more in-depth qualitative data collected through subsequent focus groups. This design allowed the researcher to better interpret and explain the quantitative data by exploring general and special educators', counselors', and ESL teachers' perceptions of the causes of academic difficulties experienced by students who are CLD, to understand how their perceptions of the causes of academic difficulties experienced by students who are CLD influence their use of evidence-based practices and making special education referrals for students who are CLD. Results of the study identified that limited English proficiency was rated the highest cause, while low intelligence was rated the lowest cause of academic difficulties experienced by students who are CLD. Qualitative information obtained through the focus groups identified four themes: Instructional Strategies, Special Education Referral Process, Experience with Students who are Culturally and Linguistically Diverse, and Teacher Resources which provided better interpretation of the quantitative data. Implications for decreasing overrepresentation of children who are CLD in special education and reducing inappropriate special education referrals for students who are CLD are discussed. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]