Design thinking is a methodology used by teams to solve complex problems, and find solutions for clients. It draws upon logic, imagination, intuition, and systemic reasoning, to explore possibilities of what could be—and to create desired outcomes that benefit the end user.
At it’s core, it puts your customer centre stage of the strategic process.
Many organizations, authors, and institutions have rallied around this concept. Likely the most notable are IDEO, Roger Martin of the Rotman School of Management and the general d-school crowd like Stanford.
Many confuse the title with that of graphic design. But in fact it is closer to conventional strategic planning, when done well.
IDEO has probably owned the space more than others with its Human Centred Design approach and tool kit. A Field Guide To Human Centred Design can be found here https://www.ideo.com/post/design-kit