Pros
Chemonics is one of the top USAID implementing partners and provides one of the best professional development programs in the industry. If you're able to make it though some of the cons (see below!) competent and qualified employees will be rewarded with field opportunities and opportunities for technical assistance. Chemonics has one of the best benefits package in the industry (NB...in the industry, not in general!) and compensation is generally comparable to other organizations.
Cons
You have a 50/50 chance of having a weak supervisor, so practice "managing up." If you're a laid back wait-and-see personality this is not the company for you. You have to push - aggressively - for opportunities, feedback on your performance, promotions, salary increases, etc. Many many many people complain about working long hours at Chemonics. I don't know if these people haven't worked anywhere else and think the rest of private sector is going home at 3:30 on a Friday, but this is the real world. Deal with it. Bottom line: if you have effective time management skills you will work an average 45 hour week about 10 months out of the year. For two months you will find yourself slammed with business development / proposals and there's really nothing you can do about it (unless, of course, you don't want to work on proposals and then you can kiss your career goodbye). Biggest complaint: pay, bonuses, and promotions are not directly linked to performance. This is a symptom of weak mid-level management (i.e. at the Director level...Directors lead projec management units and report to the Senior Vice Presidents who make promotion / raise / bonus decisions). People who put in long hours are automatically considered "hard workers" and seen as more competent, and are thus financially rewarded...even if the long hours are the result of them actually being inefficient or inept!