Procure to Pay Purchasing Methods Process a purchase order, non-purchase order invoice, Purchasing Card, or reimbursement. Available Contracts and Suppliers Approved suppliers deliver best value, meet University policy, and include Central Procurement support. Anchor Destination Policies View the Penn State Central Procurement policies that align with procure-to-pay. Competitive Bidding Understand competitive bidding requirements, thresholds, and documentation for compliance. Tax Exemption and Credit Download a PDF certificate or credit letter to share with a supplier before a purchase.