On two occasions now we've had to go through sleep training with Wee Rose. The first time was well the normal first time just getting her to sleep through the night, the second time was after a prolonged illness that led to her learning new sleep associations.
The first time we went through sleep training Wee Rose was sleeping in her crib and having no problems falling asleep but she was still waiting up every 4 hours or so. She was 5 months old. I borrowed from the library a book called The Baby Sleep Solution. Though the book was very breastfeeding friendly I was at this point having difficulty pumping while at work and we decided to switch to formula during the day. One method the book said to do was increase of food per feeding during the day and gradually decrease the amounts per feeding at night. It took a few days but soon Wee Rose was asleep 11 - 12hrs. It was so easy and so glorious.
The second time was much tougher and we're still working on it a bit. This time Wee Rose had formed sleep associations with sleeping in her swing. While ill we had let her sleep in her swing to help ease the pains of her congestion. She was congested for over two weeks though and at the end of it refused to go back to sleeping in her crib. We made a hard call and pulled out the big guns. I had previously bought Dr. Ferber's book when we were looking for solutions the previous time but it didn't arrive until after she was sleeping through the night, so I never read it. This time I read it from cover to cover.
Dr. Ferber gets a bad rap often. I thought his book was going to be very harsh just saying to let our baby cry and cry until she just gave up on us. It expressly says no NOT to do that. Yes there is a progressive stage of time where you let them cry but crying isn't the point of it all. The point is for the baby to associate what you wish them to (in our case and most parents it was her crib) with sleep. If you let them cry but they never fall asleep then all of that crying was worthless. Once I thought of it that way it really changed my few. I didn't want my baby to cry at all but if it was going to happen then I certainly didn't want her crying for more than was needed. So once she was fully better I settled in for a hard night. That first night we went in like advised after 5 min then 10 minutes and then she was asleep. What was harder was 2 hours later she woke up and it took 20 minutes for her to get quiet to just wake up 10 minutes later and start over. We all survived and she feel asleep. Since that night it hasn't been perfect but more times then not she sleeps in her bed. Last night she went all night without waking either for the first time in awhile. I think she just went through a growth spurt because on Sunday - Wednesday nights all it took was a bottle and she went right back to sleep in her crib.
The moral is that though CIO seems tough what is tougher is instead of a few nights of crying going through months of it. It can work and everyone can be happier for it. Remember the point isn't to cry but to fall asleep.