HBR: Ask an expert: Why Am I Not Getting Promoted?

What do you do when you enjoy your job, have worked for 4 years in role without any negative feedback, and still can't seem to secure a promotion?
 
 In the "Ask an Expert" column, I was asked by Harvard Business Review Ascend to provide guidance for a reader:
 
  How do I deal with the anxiety around promotions?
  What should I do to gain more constructive feedback on what I can do to improve myself for a promotion?
  How do I know if I should be more patient about a promotion, or move on?
 
 Take a read and I look forward to your thoughts and additional ideas.