If you do a search, you will find tons of threads on this subject. At 7 mos, I'd get either a soft structured carrier like the Beco, Ergo or Patapum or a mei tai like the baby hawk. If you want to carry your baby on your back, the soft structured carriers cannot be beat. They are so comfy. For a front carry, I much prefer a mei tai. I LOVED my babyhawk. We took it to dl when ds was 7 mos and I carried him it the whole time.