Thayer Street Partners provides flexible growth capital through highly customized, non-control structures like preferred equity and debt with warrants that protect downside risk while preserving equity upside for founders, positioning itself as an alternative to traditional senior debt and control buyouts for lower-middle-market recurring-revenue businesses that often don't fit traditional lenders or buyout firms. The firm built its platform through standalone special purpose vehicles before migrating to commingled funds and focuses on roll-up platform strategies within services and specialty finance, drawing on the founders' Goldman Sachs Special Situations Group background to offer structured equity solutions in nontraditional situations.