HIVIAIDS infection in the workforce is a threat to the South Africa construction industry. A web-based questionnaire survey of construction firms in the Western Cape explored workplace HIVIAIDS interventions. Extending previous quantitative analysis, thematic analysis is used to explore the qualitative verbatim comments offered by survey participants. Five themes are identified: understanding the problem of HIVIAIDS in relation to the firm; interventions by the firm; barriers to interventions; success of interventions; and future intentions. Many firms are still in denial regarding the threat of HIVIAIDS. Interventions focus primarily on awareness and prevention campaigns, with less attention given to treatment programmes. Some firms, notably larger firms, have developed HIVIAIDS policies, and have implemented or outsourced awareness, prevention and treatment programmes as a good business model. Barriers to interventions relate to lack of senior management support, risk of breaches of confidentiality, stigma, and anticipated cost. Success of interventions is uneven, but firms not currently mounting intervention programmes indicate their intentions to do so in future. A cascading and unified national, industry-level and organisational strategy is needed. Firms successfully managing their HIVIAIDS response should share their experience with those firms struggling to re~pond or-which are not yet doing so at all.