Herzfeld Advisors began as a research firm for the then little-known closed-end fund industry, supplying closed-end fund data to investors, regulators, academics, and other industry participants. It later moved into investment advisory and created the Nasdaq-listed Herzfeld Caribbean Basin Fund, running closed-end fund strategies across fixed income, municipal bonds, balanced allocations, and preferred shares and senior notes.

The adviser specializes in closed-end funds, using research it produces on the sector to build portfolios with exposure across asset classes such as fixed income, municipal bonds, CLO equity, and real estate. That research-driven approach is positioned against the templated, formula-driven allocations of other investment advisers, with clients including pension plans, state treasuries, university endowments, insurance companies, family offices, and ultra-high-net-worth individuals.