Pros
American Tower is a stable company, in a booming industry, with a good growth trajectory. It is full of smart people who care about the work and the success of the company. Every full-time employee is a shareholder, which is a great motivator. The company believes in the professional growth of its people and provides an annual development stipend for each team member. There was good work/life balance, and leadership was generally open to adding staff to account for increasing workload as the company grew. They always made sure everyone had what they needed to do their job. The office is beautiful, clean, and well managed. The office manager does a wonderful job of ensuring the workspace is conducive to productivity.
Cons
It's a large corporation, which comes with downsides. It's a hierarchical organization, and there's a lot of red tape to get anything done. Most employees aren't empowered to make decisions, with almost everything requiring the sign-off of a VP or SVP. Many teams seemed top heavy - a lot of bosses and not quite enough people to do the day-to-day tasks. There was an issue with lack of recognition for the time/effort it takes to get things done. The overall compensation package was solid, but base salary was on the low side. Hard work and high-quality performance were often recognized but not rewarded. It felt a little cliquey, with certain people seeming to have access to more career growth opportunities than other high performers. The leadership team never seemed particularly aligned with each other, which can be confusing and demotivating for employees.