Since the first report of pig cloning there has been a continual push to increase the efficiency of SCNT. While some improvements in efficiency have been made, overall term development is still low. It is anticipated that understanding the mechanism(s) of remodeling and reprogramming
during SCNT will provide clues to improve the efficiency. Recently, a key remodeling factor during SCNT in pigs was identified. Similar efforts to identify other remodeling factors will likely aid in understanding and subsequently improving the efficiency of SCNT. Moreover, a continuing effort to develop more efficient pig embryo culture media would ultimately increase the efficiency of SCNT by producing more viable embryos. A number of unanswered questions remain, but a combined approach as described above will lead the way to improving the efficiency of SCNT.