Howard Marks co-founded Oaktree Capital Management in 1995 and built one of the largest distressed-debt and credit-investing firms in the world. Across decades of investor letters and memos — published continuously at oaktreecapital.com/insights as Oaktree's investor communications, with the historical archive going back to the early 1990s — Marks developed and refined a framework for thinking about market cycles and investor psychology that has become one of the most-cited analytical frameworks in modern macro and credit investing.

The framework was synthesized in two published books: *The Most Important Thing: Uncommon Sense for the Thoughtful Investor* (Columbia Business School Publishing, 2011) and *Mastering the Market Cycle: Getting the Odds on Your Side* (Houghton Mifflin Harcourt, 2018). The framework is structurally about three interrelated cycles operating simultaneously: investor psychology, the credit cycle, and the real-economy cycle. Marks's central analytical question — repeated across decades of memos and the two books — is, where are we in the cycle, and what does that tell us about positioning?