Dear Don,
There's no need to worry. There are many children who are three who have not yet achieved toilet training. Be patient and supportive - your daughter will be fine, as development runs its course.
Be sure to keep presenting the option of the potty, without
pressurePressure ulcer. Keep a simple sticker chart on the wall, and let your daughter know that, each time she uses the potty, you will place a sticker on the chart and she will receive a modest treat.
Also, use the available children's literature on the subject. As children are ready, they very much enjoy these stories.
If you'd be interested is reading other questions and replies on this topic, utilize the SEARCH function in this Forum and type in Toilet Training or Potty Training.