Exhibit 23.1 Consent of Independent Accountants We hereby consent to the incorporation by reference in the Registration Statements on Form S-3 (No. 333-74613) and Form S-8 (Nos. 333-80255, 333-72441, 333-69855, 333-48779, 333-48767, 333-48765, 333-27983, 333-04291, 33-64094, 33-64278, 33-93106) of Express Scripts, Inc. of our report dated February 4, 2000, relating to the financial statements and financial statement schedule, which appears in this Form 10-K. /s/ PricewaterhouseCoopers LLP PricewaterhouseCoopers LLP St. Louis, Missouri March 27, 2000