Small events (10-30 rooms): start 3 months ahead, send RFP at 10 weeks, sign at 6 weeks. Medium events (30-100 rooms): start 6 months ahead, send RFP at 20 weeks, sign at 12 weeks. Large events (100+ rooms): start 12 months ahead, send RFP at 40 weeks, sign at 24 weeks. Starting earlier always gives you better rates and more options.