Of course, when things are gone about in different ways (adoption rather than conception), there are many questions. I thought I would put some of our answers out there in a series of FAQ posts. Of course, our decisions/reasonings run sometimes deep; therefore, the answers here may be incomplete.
Why are you adopting?
I have long been intrigued with the imagery that God draws between our human lives and His relationship with us. I was constantly drawing reminders of this relationship from Josh and I's courtship and marriage. I am often reminded of His fatherhood through interaction with our boys. It is a beautiful thing.
When thinking of the greatest gift: our salvation, I can't help but think of the amazing adoption that took place when He took us in as His children. (John Piper presented a wonderful talk on that subject). Of course, with a love for symbolism, the message and reality of adoption is a beautiful thing to me.
For more concrete reasoning, we love being a family. I consider it my greatest calling and, really, my best chance for making a difference in the world. There is no one I will impact more than my family. We have (since before we were married) always talked of having a large family and possibly adopting as well. We still feel that way. For me, the concept of adopting and the thought of loving a child who didn't start as my own is natural. It just seems right.
Once, while talking with a lady who had adopted, I threw out that we were hoping to adopt. She looked at me with confusion and said: "Why?" As if to suggest: "You can have children of your own...why would you wand to adopt?" Well, adopting for me is not a "plan B" it is a desire. And that is our reasoning for adopting.
I recommend listening to the above link on adoption.