We estimate the impact of workforce diversity on productivity, wages, and productivity–wage gaps (i.e., profits) using detailed Belgian linked employer–employee panel data. Findings show that educational (age) diversity is beneficial (harmful) for firm productivity and wages. While gender diversity is found to generate significant gains in high-tech/knowledge-intensive sectors, the opposite result is obtained in more traditional industries. Estimates neither vary substantially with firm size nor point to sizeable productivity–wage gaps except for age diversity.