Typically, Delta Green recruitment operates like this. 

I. INTRODUCTION

1) Non-DG Federal Agents encounter the mythos in the course of their normal investigation/daily life.
2) Delta Green gets wind of it through their network of contacts.
3) Delta Green handles the matter or assists the ignorant Federal Agents, who are usually appropriately grateful to have this Deus ex Machina to help them.


II. ILLUMINATION

1) Delta Green contacts survivors of phase one with an offer for them to participate in a new "assignment." The entire pass is designed to give the potential recruits the feeling that something paranormal is occuring, when, to the best of Delta Green's abilities, it is not.

2) The Potential Recruits' behavior during this investigation is monitored. If they do not jump wildly at any irrational theory and conduct themselves in a responsible, rational manner, then they are marked to be approached with an offer of membership in the cell structure.

3) Often, a redacted version of Delta Green history is explained to these agents (convieniently neglecting to mention the illegal nature of the conspiracy). This is when they get a code name and place in the Cell Structure, a laptop with heavily encrypted access to the Delta Green Secure Server network, calling cards linking them to elta Green's covert telephone communications system.

At this meeting, Delta Green likes to have individuals with credentials from as many federal agencies as possible. Specifically, care is taken to have people from the CIA, FBI and NSA present, along with the highest ranking representives from the US Navy, USMC, US Army and Air Force that can attend. The idea is to overwhelm the new agents with rank and credibility. Paul MacLester (Agent ERNIE) of the National Security Council is the most likely agent to organize these meetings.


III. IMMERSION

After this, the newly minted agents will be sent on more and more dangerous investigations, with every success leading to additional responsibility. Eventually, the burden is likely to break their backs.

Discovery of the vast scope of Majestic-12, the illegal nature of Delta Green, and the endless horrors of the mythos await them. Once past the sundered veil, there is no returning to the other side of the curtain. They are no longer the audience, content to watch and wait. They are now actors, and they will all find a part to play.


Credits: Kenneth Scroggins (MIB)