From birth both our babies slept in a bassinet in our bedroom - I found this the easiest arrangement for us as I could hear when they woke up and take them into bed to feed and then settle them. When I had Harry (our first) I was paranoid about having him sleep in the bed with us and I ended up spending a lot of time rocking and soothing him at night, as in his first weeks he was a generally unsettled newborn and also colicky.
When we brought Grace home I had no such qualms about her sleeping in bed with us. Being our second baby I was a lot more relaxed with her and she was relaxed too I think. I would put her down to sleep in the bassinet and when she woke at night I would feed her in our bed then if she went back to sleep I would put her back in the bassinet. If she was looking like she wanted to stay awake I would settle her next to me in bed in the crook of my arm and we would both go comfortably off to sleep. She grew too big for the bassinet at around 4 months so I moved her into the cot in her own room. She has been fine in there and settles well at night. We also did this with Harry. Our bedroom is not big enough to fit the cot and we felt that it was better for them to have their own space for sleeping.
This has worked well for us, although around the time Grace was born Harry started refusing to sleep in his room and screamed if we left him so he started sleeping on the floor in our bedroom at night. He did this up until a week ago when we finally transferred him back to his little bed in his bedroom, and he has handled that well and now goes off to sleep on his own. He is older now though and he has had time to adapt to Grace being around and I think he is finally feeling secure again.