Pooches: How to Integrate a Second Dog

A lot of people have been asking how we picked a second dog and how Miss M and Mr B became such a compatible duo. We did put a lot of thought into how we would add a second dog to our family, so some of it was pre-planning, some of it was careful integration, and some of it was just luck. We know all dogs have different personalities and quirks, but here are some things that worked for us:

Letting Them Choose and a Proper Introduction

Somewhere along the way we realized while we made the decision to get a second dog, the choice of dog was really up to Miss M. There were a couple of dogs that I really wanted to adopt, but Miss M didn't approve. We all know how bossy Miss M can be, so it was important for us to find a submissive dog. We wanted an opposite gender dog for all the reasons we originally wrote about here. We also knew we needed a dog that was more compatible with our lifestyle, so we began searching for a mellow, older pooch. Mr. B was 5 years old when we adopted him!
To set the pooches up for success, we also knew it was very important to have a proper introduction.  We take them to a neutral introduction and have them walk by eachother (never head on) to gauge their interest and watch for body language. We do a couple of walk-bys to see how they react, with the end goal of having them walk together as a pack at the end. Kate, from Twenty-Six to Life, wrote this really good detailed post about dog introductions.
Miss M approved of Mr B enough to make him into her own personal pet. 
Fun Fact: On our search, Miss M's originally met and fell in love with an overweight beagle named Butters. She settled for Mr B as a close second.

House Rules for Success

Mr B wasn't always Miss M's furniture and it actually took time for the pooches to become comfortable with one another. (This is the funny video documenting the exact moment when they first became 2 dogs in a crate; unbelievably, Mr B made the first move!)
 We made sure to keep things quiet and low-excitement while Mr. B integrated into our household. To eliminate the possibility of resource guarding, we fed the dogs separately in their crates, kept the water bowl separate, eliminated treats and toys and kept affection low-key. We also kept plenty of dog beds around--so nothing was high value--and we kept the pooches crated separately when we weren't home.
We would also give Miss M 'alpha' status by feeding her first, letting her exit and enter first, and other high value rules. We didn't scold the dogs if they needed to correct (sharp bark if they didn't like the other dog's behavior) because it's something the dogs work out among themselves. 
It was also important for us to walk them together. Much like the idea behind SociaBulls, group walking is a positive social experience.

The Value of Fostering 

 If we had to do it over again, we would definitely foster a dog before making the adoption leap. Fostering lets you recognize how a dog might fit into your home without the long-term commitment, especially if you're transitioning from one to two dogs. Plus a great side-effect of fostering, is that you are directly saving a life.
We also wrote this post about how to successfully integrate a foster dog into a multi-dog household.

These are just some experiences we've had. What are some other things you've learned about adding another dog to your family?