Despite considerable research effort and significant advances in sequencing technologies, the majority of disorders of sex development (DSD) cases still lack a molecular genetic diagnosis. While coding variants have been discovered in known and candidate DSD genes, comparatively little is known about copy number variations (CNVs) affecting both coding and noncoding regions. Due to rapidly falling costs of whole genome sequencing, many more CNVs in individuals with DSD will be identified. These CNVs may explain a significant number of hitherto undiagnosed cases of DSD. In this review, we provide an overview of CNVs that are known to cause DSD and discuss approaches to identify and verify causative CNVs.