Temporarily placing a hold on a protocol that had previously been approved. During a suspension no new participants can be accrued, no research interventions may occur (unless necessary for the safety and well-being of the enrolled participants) and no follow-up can be conducted unless it is in the best interest of the participant and approved by the IRB. A suspension would normally last until the IRB has reviewed relevant materials and have made a decision to Terminate the approved research protocol or lift the suspension so research may resume.