Adaptable Product Discovery is a well-documented framework developed and published by Tim Herbig. It provides even more guidance to the various phases of Product Discovery than the Double Diamond model.

A Practical Guide for Agile Teams

This is the original title of the web site and the original is constantly being updated:

Product Discovery: ‚ÄčA Practical Guide for Agile Teams (2021)

In a nutshell, Tim breaks down the complete Product Discovery into 6 phases:

Phases of Product Discovery

Just like Double Diamond, this framework also distinguishes between the problem space and solution space:

Contrary to what the initial hexagon suggests, Product Discovery is rarely a linear process. Rather, sometimes it is ok to cut corners. In other situations, it may be required to take a step back and start fresh because the team might got stuck: