The league is contested by twelve teams from the Northern California and Rocky Mountains regions, who play a regular season split into two halves.

Gradually, it returned to Montana and Utah, and expanded into Colorado and the Canadian province of Alberta by 1974, and since then has consistently had eight or more teams competing.

As of the 2024 season, four teams from Montana, three from Colorado, two from California and Idaho each, and one from Utah compete in the Pioneer League.

Nineteen franchises have competed in the league across its 86-year history, with the Missoula PaddleHeads, a current team that joined as the Pocatello Cardinals in the inaugural season, being the longest-tenured.

The original six teams were the Boise Pilots, Lewiston Indians, Ogden Reds, Pocatello Cardinals, Salt Lake City Bees, and Twin Falls Cowboys.

With players in short supply due to World War II, the league suspended operations for the 1943 through 1945 seasons.

In 1948, the league expanded by adding two teams in Montana; the Billings Mustangs and Great Falls Electrics.

He mediated the restructure of Minor League Baseball's governing structure in 1992 and was an inaugural member of the MiLB board of trustees from 1992 to 1994.

His publications include: Sports Law: Cases & Materials (with Ray Yasser, C. Peter Goplerud, and Maureen Weston) (7th ed.

LexisNexis 2011),[13] Thunder on the Road from Seattle to Oklahoma City: Going from NOPA to ZOPA in the NBA, in Legal Issues in American Basketball ch.

IV (Lewis Kurlantzick ed., Academica Press 2011),[13] and, The Fundamental Nature of Professional Sports Leagues, Constituent Clubs, & Mutual Duties to Protect Market Opportunities: Organized Baseball Case Study, in Legal Issues in Professional Baseball ch.