The executive director sat across from the board chair in the agency's cramped administrative office, a thick folder of contractor invoices and inspection reports spread between them. Three years had passed since the renovation wrapped up, and what had seemed like minor settling in the foundation had revealed itself as something far more serious. Water now seeped through the basement walls after every heavy rain, pooling in the storage area where the agency kept supplies for its vulnerable-population programs. The structural engineer's report, commissioned just two months ago, traced the infiltration to improper foundation waterproofing and inadequate drainage installation — work that had been subcontracted out during the original project. The general contractor, when confronted, had pointed fingers immediately: the subcontractor had handled all foundation work, the subcontractor had assured everyone the membrane was properly installed, the subcontractor had signed off on the drainage specifications. Now the agency faced a choice about whether to sue, and the contractor faced a choice about whether to drag the subcontractor into any resulting litigation. That second choice — how a defendant brings a third party into an action — involves a precise set of procedural requirements that, if mishandled, can foreclose the defendant's ability to seek contribution or indemnity from the party actually responsible for the loss.