Elaine, there is a difference between "evidence based" and certified as "best practices." I ran a study of a group of Adlerian based parenting programs, almost all of which used the Positive Discipline program and it was published in 2003. It showed significant changes. Since then, since we do pre and post surveys with all of our classes we have collected more data showing increased connection and decreased harshness in families across lots of different backgrounds. So yes, there is evidence, and no it is not best practices because the criteria now includes formal randomized control groups. And we don't have the budget for that.