Macroeconomía (19th Spanish edition of Economics)

The Spanish volume of Samuelson and Nordhaus's Economics, the most widely read introductory textbook in the history of the discipline. For a product director its value is not the equations but the framework: GDP, inflation, unemployment, business cycles, and the long argument about what markets do and don't do well. Most product decisions are made inside macroeconomic conditions — recessions shift what customers will pay, inflation reshapes pricing, growth cycles determine hiring — and most product directors argue about them without the basic vocabulary. Samuelson is neither the deepest economist on the shelf nor the most contemporary, but his textbook is the canonical starting point that gives the rest of the library a common frame. Keep it as a reference rather than a read.