Cardano is lead by three organizations formally described here. We give a basic breakdown of the organziations below:
IOHK is leading the software technology development. It has a contract to lead Cardano engineering efforts through 2020. IOHK recently announced plans to move its headquarters to crypto-friendly Wyoming.
Emurgo is the commercial venture arm of Cardano - tasked with building out relationships across the globe. Based in Japan, Emurgo has offices in Indonesia, Hong Kong, UK, and NYC.
The foundation is responsible for a wide range of Cardano activities including community building to advocacy on regulatory efforts around the globe. (Yes, there was drama in 2018, but we are moving forward!)