How do you maintain a balance of selfless service and career progression?

Unless you are -exceedingly- lucky, nobody is going to fight for your career advancement for you, so you have to fight for yourself. Selfless service doesn't mean letting opportunities pass you by.

If you really believe in selfless service, get your promotions, and use them to lift up others. Get your education, civilian and military, and use them to teach others. Look at Army Career Tracker to see what assignments can help you move along. Get ambitious in your career field, volunteer for boards, competitions, etc-- and share what you learn along the way with the new Privates and Specialists who have the same desire.

I've been in E7 slots for years, and am still stuck as an E5. I know the pain. Don't get stuck in a rut, fight to move forward, and bring everyone you can with you.

Making yourself a better Soldier and ready for promotion is not necessarily in conflict with selfless service. In fact, there is great synergy there.
You become more valuable to your unit, and you will earn you way up the ranks.
Just ensure that the career progression doesn't become a priority over your Soldiers, and you'll be fine.
You men always come first.

Easy, you use selfless service as career progression. I have seen a lot of ass kissers, brown nose individuals and D*** S***ers my entire career and they know who they are but you have to not let at whats going to get you the edge or how can you look good by undermining this individual but you have to put every thing and one that you are responsible for first and always strive to make your organization better and more efficient for everyone. Anyone can wear a SGT rank but it's until that individuals actions are observed is when you know if they're an NCO by their leadership because thats what we do and who we are, "professional, Noncommissioned Officers, leaders!".

Your best bet is to follow your dreams. You are serving your country, attend advanced education is great. You can combine the two. I served for over 30 years and left the military with two degrees. If you decide to get out then do it. Either way you have served and that is more than most will ever be able to say. God Speed.

I'll say it like this because I'm already experiencing it myself: earning the higher pay grade and higher education puts you in a position to serve selflessly better than the previous lower rank. Once you're a SNCO in particular you can literally influence the careers of your subordinates. It's up to you whether that influence is for the better, or worse. Don't worry about acknowledgement of it through medals, letters, etc. Depending on what you did it gives you a very nice edge when you interview for a good-paying job in the civilian world. Case in point: I'm doing things in my unit that are making the Marines put more faith in me to make something happen than the very people paid to make the same thing happen. If you can make that happen with your peers and your subordinates then you are already serving selflessly, and trust me you will get a great return in that investment of your efforts.

SPC (Join to see) An equally hokey answer, nothing and everything.
I did everything that as asked, went to every school offered even when it was inconvenient, bad timing at home, just back from the field, deployment
Nothing: I did not much to take care of my career progression other then everything needed to do what was asked the best possible way, never said no to a task, but was open and honest and said what it would cost to make it a yes, what was needed, or here is another way, solution, idea.

It's somewhat cliché, the most important job you'll ever have is the one you have now. Truly, dedication to your unit, mission, and Service will yield positive results in terms of promotion, school selection, and other things your supervisors control. You should volunteer for training and education opportunities related to your MOS when they become available. Take full advantage of on-line training courses related to your MOS or areas in which you are interested as future employment in or out of the Army. If you have time in you personal life and your work schedule allows, consider taking advantage of post-secondary education through local colleges or universities. As long as you are learning information that is related to your MOS, then you are helping yourself, your unit, and the Army overall.

There is nothing wrong with ambition as long as it doesn't get to the point of selfishness. Do your job. Do it well. Take care of your Soldiers to your right and left. Support your chain of command and NCO support channel and those things will come. Or you could just be a Command Specialist Major lol

Excel at what you are doing and get all the education you can. Whenever I had to fill quotas or opportunities with my Marines, I'd pick my best people who I thought would stand out in that position and reinforce the units reputation. Same criteria when it came to promotions and career enhancing opportunities, the best were at the head of the line. It hurt often because they left a void that was sometimes hard to fill, but I couldn't stand between them and opportunity when they'd given their all for me and the init.