Taiichi Ohno was the creator of the Toyota Production System (TPS). Ohno's concepts of flow, pull, WIP reduction, and batch-size-reduction in manufacturing are foundational to what Reinertsen translated into product development. The wip-constraints and flow-control ideas in principles-of-product-development-flow are direct intellectual descendants of Ohno's manufacturing insights.
However, Reinertsen's relationship to Ohno is not one of simple adoption. Reinertsen's "second generation lean" critique argues that mechanically applying Ohno's manufacturing tools to product development misses the underlying economic logic. Manufacturing has low and predictable variability; product development has high and valuable variability. Ohno's approach optimizes for repeatability and waste elimination; Reinertsen's managing-variability framework argues that in product development, some variability creates value and should not be eliminated. Reinertsen seeks to recover the economic reasoning behind TPS rather than copy its practices — understanding why the tools work so they can be adapted appropriately to a different domain. liker-toyota-way provides the most comprehensive account of Ohno's system and is useful context for understanding what Reinertsen builds on and argues against.