General information on joining a project's virtual organization (VO).
Virtual organizations (VOs) are sets of grid identities, organized in groups, with roles assigned to individuals. Typically, these are groups of people that sit at different physical locations all over the world to achieve a common goal, such as finding QGP or the Higgs boson.
Before you can start using grid resources, you have to join one of these organizations, as they have an agreement with collaborating universities, institutes, and national labs to use their computing resources. You will send a request to join a VO, which will be approved by a representative of your experiment (you can join only the VO for the experiment of which you are a member). Then your "distinguished name" (DN), or your unique identity on the grid, will be added to the list of DNs for your VO, and all collaborating sites all around the world will recognize you as being part of your virtual organization.
Joining a VO
US ATLAS users can (and should) begin Step 1 of the VO application process while waiting for their grid certificate.
Members of other experiments and groups may find that VO membership is no longer needed for their purposes. Please check with your experiment liaison or group leader for details.