Best Language Institute is located in Kangnung (Gangneung), in South Korea's Kangwon (Gangwon) Province. It's one of hundreds of small, independent commercial English-language schools (hagwons) in South Korea.
Best was originally a family-run hagwon. It was founded by the brother of Margaret's director, Mrs Kim Eun Ryung. Mrs Kim sold the school in September of 2010. I have no idea who owns it now, or what it's like to work for Best Language Institute today.
When Margaret worked there in 2000-2001, the school had 6-8 teachers, one usually a native English speaker. Classes met 6 hours or more per day. The school taught mostly grade school kids, but it also had evening classes for adults. Margaret was asked to do a little offsite tutoring - for one private student and a business. You can read about that in her journal.
In 2000 and 2001, Best were crammed into the downtown Kangnung (Gangneung) office building shown on the left above. It was really convenient, about a 5 minute walk from Margaret's apartment. In the Spring of 2003, BLI moved to a larger, more modern building on the outskirts of the city. That's it in the far right picture above (the banner hanging down the middle of the building boasts that they have an American teacher).
The new digs are much nicer. More importantly, they're closer to the city's newest apartments - just as in real estate, it's all about location. This neighborhood is more affluent. That means more students, and parents who can better afford to pay their tuition.