The Immersion Composition Society (ICS) is an underground network of composers, organized into independent groups, called lodges, who periodically spend one or more days composing unusually large volumes of music for the purpose of creating raw material for their new projects. There are several dozen publicized lodges in the U.S, Canada, Europe, and South America. The book The Frustrated Songwriter's Handbook details the ICS approach to creative songwriting.
The Immersion Composition Society was started in Oakland, California by two songwriters, Nicholas Dobson and Michael Iago Mellender. Noticing that they were spending large amounts of time thinking about music and waiting for inspiration to strike — instead of actually writing music — in early 2001 they developed a new songwriting method that involved composing prolifically while trying to avoid any kind of self-editing or self-consciousness.
The result was a songwriting "game" that took place over the course of a single day. They both began to play it compulsively. Within a year, Dobson and Mellender had formed a society of songwriters, and this game — which came to be called the "20-Song Game", was its central activity.
The ICS is made up of local chapters called "lodges." An ICS lodge is not unlike a small, local secret society of songwriters. The lodge exists as a way for all of the members to force themselves to write as much music as possible. The privacy and secrecy of a lodge are there to create a "safe" environment for musical experimentation, free of unwanted criticism and negative social pressure. The members of an ICS lodge do their best to support each other completely, and each member is encouraged to indulge any musical whim or subject matter — no matter how ridiculous or questionable it may seem to the songwriter at the time. Each lodge has a "lodge head," and any number of members, averaging up to a dozen.
The 20-Song Game works like this:
As more lodges were formed, ICS members from all over began to create regional variations, session themes, and new games with names like "Hat-Lib," "Spooling," and "Composer Tennis". Elaborate track swapping also became popular during this period, especially as a form of international musical collaboration. By now it had become common for Society members to personalize the 20-Song Game over time, cycling through periods with higher and lower volume goals. This was the point when ICS methodology started to evolve into a larger system for songwriters that could be used to tackle more or less any goal that the user wanted, including low-volume goals such as developing production, arrangement, and craft. A popular example is a member invoking "album clause," where for the purpose of working toward an album project, the member suspends some of the ICS customs at his or her whim.