How do you wean a toddler off a pacifier?

Take it away completely. It may be difficult and there will be a fair amount of tears but it's really the only way to stop use all together. Offer another object for comfort, a blanket or toy and even though he or she is very young: talk to your child (you are a big boy/girl now, etc) It may not seem like it's working but encouragement does it's part. I had the same problem trying to get my 1 1/2 year old weaned off bottles (approx four months ago) and just had to grit my teeth and bare it. It took less than a week for him to adjust. Good luck!