The theory discussed in the article explores why firms exist, where their boundaries lie, how they are structured, and what influences their actions. It seeks to understand why some transactions are kept inside firms instead of happening through markets. The research delves into the reasons behind firms' organizational setups and the factors driving their performance. Key questions include why firms form, why they do some things internally while outsourcing others, and how their internal and external relationships shape their activities. In essence, this theory looks at why companies function the way they do and what factors shape their decisions about how they operate, whether inside or outside the company.