how many episodes are in season 4 of agents of shield
22
Agents of S.H.I.E.L.D. (season 4)
The first episode premiered at a screening on September 19, 2016, with the season then airing for 22 episodes on ABC, from September 20, 2016 until May 16, 2017. 
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Agents of S.H.I.E.L.D. (season 4) [SEP] Introduction
The season is also affected by the events of the film "" (2016), and continues storylines established in the canceled series "Agent Carter". The first episode premiered at a screening on September 19, 2016, with the season then airing for 22 episodes on ABC, from September 20, 2016 until May 16, 2017. The premiere debuted to 3.58 million viewers, down from previous season premieres but average for the series. Critical response to the season was positive, with many feeling that each pod was better than the last and in particular praising the visual effects and tone of "Ghost Rider", the writing and acting of "LMD", and the character development and political commentary explored during "Agents of Hydra".