SMAP is one of the longest-running and most iconic Japanese boy bands. Debuting in 1991, the group took the Japanese entertainment industry by storm, becoming the most successful boy band in Japanese history and the best selling band in Asia, often referred to as a "national treasure" and a "fortune and property of the country" in Japan. They achieved an unprecedented level of success in numerous genres in the entertainment industry, including music, television, film, radio, and theater, as a group and individually.

They were the first boy band to have a career spanning two decades, and was credited for changing the Japanese entertainment and music industry, in terms of prolonging longevity of boy bands and broadening careers by creating new opportunities for bands that followed. Their 2003 single, "The One and Only Flower in the World" , released in 2003, is the best selling single in the 21st century and the fifth best selling single in Japanese history and has become the most recognized song in Japan, as it appears in text books used in school and children are taught to learn the song at a young age.

They also had a weekly variety show, SMAP×SMAP, which became a ratings smash hit and went on to be one of Japan's most famous TV shows. The show ranked #1 in the annual household share ratings in 1996, 1997, 1999 - 2002, 2006, and 2016 making it the most watched television show in Japan. The episode aired in January 2002 is currently ranked #7 for the most watched Japanese variety show in history, with 34.2 million viewers. It is the eighth longest-running prime-time television program in Japan, as of 2016.