Pros
The pay is competitive and the workload is manageable. Because the company is so large and diversified, there are a lot of opportunities to work in different industries and in different roles. Average tenure at 3M is incredibly long (it's not uncommon for employees to have 30+ years at 3M) which I think speaks to the ability to have a career with a lot of variety all at one company. Additionally, there is a strong culture of learning and development. There are constantly seminars and forums for employees to engage in continuous learning and there is generally an enthusiasm around collaboration and continuous improvement.
Cons
3M is largely behind other local Fortune 500 companies in terms of benefits for working parents. If you are thinking about accepting a position at 3M and have a family or are considering starting a family in the next 5 years, I would strongly encourage you to discern whether or not you have the financial means to take an unpaid FMLA and/or use all of your vacation time for parenting leave. For maternity leave, you are eligible for 6 - 8 weeks (depending on the type of delivery) of short term disability and any additional time must be taken unpaid. The short term disability benefit varies by years of service, but for most people I know around the office who are expecting they will receive one week of full pay (provided they don't use any sick days in the last 12 months) and 60% pay for the 6-8 weeks. Any leave a new mother wants to take beyond that is unpaid. In the worst case, if a woman must go on bedrest before leave, her family stands to take a huge financial hit. For paternity leave, the official policy of 3m is that one day can be used for the day of the birth. If a father would like to take parenting leave, he can either use vacation or take FMLA unpaid. These policies are in stark contrast to what other local Fortune 500 companies offer (Target recently announced two weeks paid paternity leave and has updated their maternity leave benefits for 2016, Thomson Reuters has 12 weeks paid for maternity and 2 weeks for paternity, UnitedHealth Group also offers 12 weeks paid for maternity leave, Best Buy offers 5 weeks paid for maternity). Additionally, only two weeks of paid vacation is offered to new employees in contrast to other competitors that offer three weeks (Boston Scientific, Target, TR, UnitedHealth Group). Lastly, despite a corporate initiative called "Flex-Ability", working from home is still a faux pax and you need to convince supervisors that it can be more productive and often essential to balance the needs of work and home. There is still a strong culture of "butts in seats". In an age where companies are acknowledging that employees are retained and more productive when they are able to balance their priorities at work and home, it seems short sighted that 3M likes to boast a competitive compensation package as well as a great company for women when its policies so clearly state the opposite.