What is the most important role a step-parent can play in a step-child's life?

To be a great role model. If it is a step mom she should be the women she wants her female child to become and the woman she wants her male son to marry. A man should be just the opposite.What is the most important role a step-parent can play in a step-child's life?
To be understanding.What is the most important role a step-parent can play in a step-child's life?
During my childhood, with one step-father and many step-mothers, it seemed as if they all had one thing in common. They never seem to accept me for me.
Realize that you are the adult.. and they are the child. Understand that they will be adjusting and normally fight you just because of who you are. Be fair, be the adult, and include them in everything and you will be fine. It doesn't hurt to treat them like an adult instead of a child (in matters of responsibility too)
to know you care and to be understanding of who they are...
Let the biological parent do most of the disaplining, but also make it clear that you are an adult , and when the child is in your house, it is your rules, and make sure your spouse backs you on this and make sure the child knows that he/ she must show respect for you. In turn make sure you also respect the child, and gain some understanding of blended families. Child hood is hard and having blended families can sometime increase stress and anger. Just be a strong and positive role model. It is a long hard job, but it can be done. Both of you will benifit from this. Good luck!
friendship