This morning, Netflix kicked off the Television Critics Association Summer Press Tour with a slew of announcements, including their plans for The Defenders, Marvel's upcoming multi-series project. According to Neflix’s Chief Content Officer, Ted Sarandos, the premiere of Marvel's highly anticipated Jessica Jones series will happen by the end of 2015.
Jessica Jones will be the second superhero to join the Marvel/Netflix lineup, following Daredevil, the latter of which will see its season two premiere in early 2016. Marvel and Netflix plan on releasing each mini-series every six months, in sequence. The series will also feature Luke Cage, A.K.A. Power Man, who will later take the lead of his own spin-off series, though the date has yet to be announced. According to Screencrush, Daredevil is slated for guest roles on Jessica Jones, as well.
Eventually, the multiple shows will lead to a crossover in The Defenders, but there may be multiple seasons of certain shows before that happens, as evidenced by Daredevil's announced second season. The crossover's release date has yet to be announced.