When Donna and Jim were asked if they want an equal relationship, they answered, “Yes.” What they mean by that answer is where communication breaks down. People have widely different ideas about what equal means in a relationship.
Power usually relates to a person’s ability to influence the other towards his/her own interests or goals. Power sharing means both people’s needs are heard and met. Equal influence means couples accommodate each other. It doesn’t mean that one person is always right. And it certainly doesn’t mean that one person must convince the other of his or her rightness!
So if you are in a relationship, ask these questions:
Is each partner able to express personal goals, wishes and needs?
Do you influence one another?
Whose interests are shaping the relationship?
Does one dominate the other?
How are menial tasks like housework viewed?
How are decisions made?
Do both of you feel entitled to follow your dreams, calling, or personal goals?
If you cannot answer YES to most of these, there may be a power imbalance. And one researcher tells us that equal power is related to relationship satisfaction for both men and women. Specifically, when mutual support is shared in relationship responsibility, vulnerability, attunement and influence, couples feel good. 
In other words, when a person feels heard, is able to influence the other and share responsibilities, the relationship feels more satisfying.
 Janice M. Steil, (1997). Marital Equality: Its Relationship to the Well-being of Husbands and Wives (Newbury Park Oaks: CA: Sage, 1997).