What did your adopted parents do right? What do you wish they'd done?

EDIT: This is meant to be [Serious] replies only, sorry.

EDIT 2: I never expected this to get so many replies. I've been reading through them all, but there's a ton of responses, many very helpful and thoughtful.

A couple of things that keep coming up in answers:

• Tell your adopted kids that they're adopted - don't let them find out from someone else.
• Your adopted kids will want to learn about their birth parents. This does not mean they don't love you. Don't hide information from them, even if it's not pretty.
  
• Don't adopt kids to save a relationship. It won't work and it will harm the kid.
• Your adopted kid will inevitably throw the 'you're not my real parent' in your face at some point. Try not to take it seriously.
• If you're adopting someone from a different culture, celebrate that culture, don't hide it.
  
• Don't play favorites with your biological children, and don't let relatives do so, either. Adopted children are your family.
• You're not a hero because you adopted a child. They don't owe you anything because you adopted them. You're their parent, so start acting like it.
• If you had trouble conceiving, don't mention this story around your adopted children. It sends the wrong message.
• Adoption can be stressful for everybody. Kids can have issues. Parents can end up in divorce. Know what you're getting into.
• It wouldn't hurt to have an 'anniversary day' to celebrate your adopted child's adoption.
  
• There are several good movies to watch (Tarzan, the Jerk, I forgot one).
• Don't beat your adopted child (OH MY GOD WHY DOES THIS NEED TO BE SAID).