The closed multiplayer beta for DOOM will launch on March 31st and run until April 4th.
Those who pre-ordered a copy of Wolfenstein: The New Order when it was released in 2014 and redeemed their beta code at Doom.com/beta will have immediate access starting March 31st. Unfortunately, this is the only way to gain access to the multiplayer beta, so unless you pre-ordered Wolfenstein, you may want to try your luck through social media websites.
Additionally, a new trailer showcasing the multiplayer beta can be seen below:
