Procurement Methods

This chart summarizes the 5 main procurement methods at Northwestern University:

  Most purchases should start  
with a Standard Requisition
Other procurement methods
Type of
ordering from
All other
(from both
Vendors not
in iBuyNU
and other
For payment
of repetitive
services under
contract (from
both Preferred 
Vendors and
other external
To request a
check to pay
for services
that do not fit
the normal PO
process (such
as registration 
To pay for
goods and
services that
do not require 
a PO (such as
not to be
used for
items in

About Requisitions

Most purchases of most goods and services from outside vendors are to begin with the initiation of a Requisition in NUFinancials (either a catalog Requisition through iBuyNU or a non-catalog Requisition).

  • Requisitions must be initiated at the time the product or service needs to be ordered, not when it is time to pay for the product or service.
  • Requisitions need to be detailed and correct.
  • A Requisition ID begins with the prefix REQ.
  • A fully approved and budget checked Requisition is automatically sourced into a Purchase Order that begins with the prefix PUR during normal batch processing (no manual intervention by PRS is necessary in most cases).
  • The official Purchase Order is then sent to the vendor.
    • This process occurs multiple times per day, and once the sourcing process runs, all purchase orders are then almost immediately dispatched to the vendors. This eliminates the need and perceived benefits associated with phone orders and blanket orders.
    • The system provides an appropriate audit trail since all transactions are captured in the system specific to each individual purchase, putting the University in the best position to pay for purchases in a timely manner.
  • Starting with a Requisition ensures that an approved and official Purchase Order is issued. The Purchase Order includes Northwestern’s standard terms and conditions, which is the legal document that governs the transaction and properly protects the department/school and University.

Standard requisition types

  • iBuyNU (Catalog) Requisition
    Catalog requisitions are used to purchase from preferred vendors that are included in iBuyNU, which can be accessed from the NU Portal. Electronic invoices are automatically sent to Accounts Payable. Purchases made in iBuyNU do not have to be approved by PRS because all iBuyNU vendors are Preferred Vendors. Learn more about the benefits of using iBuyNU
  • Non-Catalog Requisition
    Non-catalog requisitions should be used for purchases from non-preferred vendors as well as preferred vendors that are not enabled in iBuyNU. NUFinancials does not restrict your ability to order from any vendor. There is more manual entry required for these orders. Orders are generally dispatched by NU’s fax server multiple times per day and invoices are sent by mail or fax to NU Accounts Payable. 

Special Requisition Types

There are three Special Requisition types. There is an option to select one of these types in the Requistion initiation process in NUFinancials.

  • Grant Subcontracts
    These requisitions do NOT require PRS approval.
    • Negotiated with the subcontractor through the Office of Sponsored Research (OSR)
    • Needs to be initiated (check the 'special Requisition type' box for Grant Subcontract in NUFinancials), which will be sourced into a Purchase Order but will not be sent to subcontractor
  • Receive by Dollar Amount
    This requisition should be used for services when the actual amount due after completion of the project may differ from the original quote that the Purchase Order was based on. This allows departments/schools to receive by dollar amount as opposed to by quantity.
    • Can be used for lengthy service projects that involve more than one invoice to be paid over several months, or if project requires deposit and then second payment upon completion of project
    • NOT to be used as a method to pay multiple invoices to a vendor when products are ordered. You must create a standard requisition for each of these orders.

Alternative Payment Methods

PRS has identified some exceptions for certain transaction types that are considered low dollar and low risk, where a formal Purchase Order may not be as necessary. These guidelines are only meant to clarify payment options for certain services: they do not change any other Northwestern or department/school policies and procedures. Please review the Alternative Payment Method Guidelines (PDF).

The following alternative procurement methods are available: