This is one of those things that is gradually being lost to the sands of time, although the Wikipedia article has a good summary:
https://en.wikipedia.org/wiki/Erhard_Seminars_Training
Basically, Werner Erhard ran something that is strikingly similar to the Lapp's "Glory Barn" operation. Eventually he abandoned openly practicing the more extreme techniques, which he called "est", and replaced it with something that could masquerade as a business seminar. (The techniques were still there, though, as evidence by the Lapp brothers doing odd things like inviting people to a business seminar and then asking them if they'd been sexually abused a few days into it.)
For an example of some of the odder techniques, one was to have bathroom breaks on a very set schedule.
He eventually rebranded as "The Forum" and later "Landmark Forum".
https://en.wikipedia.org/wiki/Landmark_Worldwide
It is quite interesting that the Amish church eventually saw the wisdom in banning this practice, and went so far as to excommunicate people who ran around promoting this. I would invite anyone who has a problem with this to debate it further.