Over the course of 4 odd years, they have established a homogenous leadership group and continue to promote individuals to higher ranks based mostly on those qualities. After working under management across various projects, you come to find that these "leaders" have very poor management skills and are not experts in their respective industries. You also find senior consultants acting as project managers who really struggle to manage a team and produce quality deliverables. As other reviewers have mentioned, many employees come from the same local consulting firm as the the person running the office.
The head of the office, who initially comes across as very caring and involved during the interview process, is really quite cold and plays extreme favoritism. Top management enthusiastically speak at office events but lack the decency to even try to familiarize themselves with all employees. You see certain teams put on a pedestal whereas some are not even given a shred of importance, and this is all based on the $$$ they are bringing to the company. Slalom dc is not as different from other consulting firms as it claims to be.
The work done has low impact/value to customers as projects are too short to even make much of a difference; But there is a high learning curve for employees. The combination of these leads to stressful and often meaningless projects.