IR35 legislation affects how contractors and consultants operate in the public sector. When bidding for government tenders, you must clearly demonstrate whether you fall inside or outside IR35. Key factors: substitution rights (can you send someone else to do the work?), control (who directs how you work?), and mutuality of obligation (are you obliged to accept work?). Public sector organizations are responsible for determining IR35 status, but your tender should demonstrate you understand these requirements and have appropriate structures in place.