The psychological construct of self-efficacy plays a salient role in students’ pursuit of a career path. Career-related self-efficacy is strongly associated with life satisfaction and emotional well-being. Most of what is known about this construct has come from research with mainstream students in the West, and considerably less attention has focused on students with special educational needs. The limited knowledge we have of SEN students’ career-related self-efficacy may be due to lack of appropriate assessment instruments with sound psychometric properties that can be used across cultures. This chapter reports steps taken to validate such an instrument, the Career Development Self-Efficacy Inventory (CD-SEI), for assessing career life skills self-efficacy in SEN students. The authors describe the use of a short form of CD-SEI in Hong Kong with a sample of SEN students and a comparison group without special needs. Theoretical and practical implications of using this instrument to assess career life skills self-efficacy of SEN students are discussed in light of current career development theories.