I believe, if first starting up a company, such as a start up and do not want to have the corporate feel to the company, I believe an organic organization structure makes the most sense to start off. You have your three main positions of CEO, CTO, COO and then other positions follow under but it is still an open environment with continuous interaction between all hierarchies. As the company grows and becomes bigger, it would make sense to have a matrix organization structure where individuals have dual reporting relationships and it also allows for more flexibility.