Should I Disclose Mental Health Conditions to a Potential Advisor Before Applying to the Program? I know there are a lot of questions about whether or not to disclose mental health issues to advisors, but the difference is that I'm asking whether to disclose these conditions before they agree to supervise me. (Thus, I don't think this is a duplicate of To break mental health condition to potential new advisor because in that post, the professor had already agreed to supervise the student.) Also, unlike the other posters who are primarily concerned with diminished productivity and/or having to take time off, my condition hurt my relationship with a professor. 

Here's what happened: How Would You React If a Student Complained to the Dept. Chair About You but Later Apologized and Disclosed Mental Illness?

Most of my problems stemmed not from the grievance itself but from persistently trying to have it dismissed, which I do not regret. However, since the university sent me a cease and desist letter (and all faculty know about the situation, or at the least know to forward any communication from me to the General Counsel's Office), they may mention or allude to this in a letter or recommendation. So it may be best for me to explain everything  prior to applying. 

Anxiety also affects me in other ways. For example, I fear flying. Since advisors often encourage their students to travel for research/conferences, she should probably know about this phobia as well. Best case scenario, she's understanding and uses this information to better communicate with me and help me avoid stressors. However, she could also decline to advise me. (If it's relevant, this is for a master's degree.)
I fear flying.


Nearly all PhD students go to conferences.  They usually go there by flying.  There is no way to hide that you fear flying.  Therefore, I suggest disclosing so that your advisor can arrange for your to participate in conferences without flying.  Disclose before you enroll, and find out if your advisor can help you be successful before you enroll.

Should you disclose before you apply?  It depends.  If you can disclose in a way that shows you will be successful in the program (e.g. "Following treatment, my symptoms are improving so I expect my future achievements will be better than my past achievements...") that may increase your chances of admission.  Show you have a plan for success.  If you disclose and indicate you cannot be successful in the program, then you probably will not be admitted.  But why would you apply if you cannot be successful?

Anecdote:  One of my colleagues disclosed a fear of flying to me when he was a PhD student.  He is now an assistant professor.  He does fly from time to time.