Nintendo Research and Development 1 (also known as R&D1) is Nintendo's oldest development team. Its creation coincided with Nintendo's entry into the video game industry, and the original R&D1 was headed by Gunpei Yokoi. The developer has created several notable Nintendo series such as Metroid, Kid Icarus, Wario Land, and WarioWare, Inc..
In 1986, several developers left R&D1 to form Intelligent Systems, which became another first party developer for Nintendo.
After Yokoi's resignation in 1996, the group was led by Takehiro Izushi. In 2005, Satoru Iwata restructured Nintendo's development resources and placed all of the internal software teams (including R&D1) under Entertainment Analysis and Development.