Exhibit 99.1

Tuesday, July 26, 2011

Merger information: Two new employee resources

Last week, we announced that Medco is entering into a strategic combination with Express Scripts to create a best-of-breed enterprise that will enable us to reach new levels of performance that simply would not be possible by either of our organizations moving forward separately.

No doubt, many of you have questions and concerns about what’s changing as a result of this merger, how and when changes will occur and what it means to you. Medco is committed to ongoing communication as we move through the upcoming shareholder and regulatory review processes, to help you remain focused on meeting the needs of our clients and patients.

Toward this goal, we are introducing two tools — a Merger Questions mailbox for employee inquiries (available now) and a centralized intranet resource containing a Frequently Asked Questions document and further information (to be available Friday, July 29). Both are detailed below.

Careful Communications

In the meantime, employees are asked to bear in mind that the company is in a period of very tight regulatory control and we must adhere to strict procedures to ensure that when communicating merger-related news to colleagues, clients and members we do not inadvertently breach securities laws and regulations.

     Therefore:

	•		Please refrain from creating your own merger-related messages or Frequently Asked Questions documents for use by any internal or external groups. In addition to the formal internal and external announcements issued on Thursday, July 21, account teams and other groups have received approved materials. Further information will be available on the internal site detailed below. Creating new documents or rewriting materials — including making even seemingly minor changes — could lead to a violation.
	•		Please refer any media inquiries about the proposed merger to a member of our Public Affairs staff. Click on the following links to access those names and to re-familiarize yourself with Medco’s policies on media relations and social media (Media relations policy — Social media policy).

Your assistance is appreciated.

Tool			How it Works
Merger Questions mailbox:			Employees submit questions to the MergerQuestions@namedco.msx.medcohealth.com via Microsoft Outlook
•   An avenue for employees to submit questions about the merger			•   Questions are reviewed and catalogued by Employee Communications
•   Click here to access			•   Responses will be consolidated on a central intranet repository (see below)
Internal SharePoint website:			Employees can log on the merger information SharePoint site at their convenience to explore all of the available materials
•   A single source for the latest updates on the merger, including leadership messages, key dates/milestones, benefits information, answers to frequently asked questions, and links to other relevant information			•   As new information is added, employees will receive alerts via Medco’s Global eMail channel •   The SharePoint site will also contain a link to the Merger Questions mailbox, where employees can submit inquiries
•   To be available on Friday, July 29

Cautionary Statement Regarding Forward-Looking Statements

This document contains “forward-looking statements” as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements, as they relate to Medco Health Solutions, Inc. or Express Scripts, Inc., the management of either such company or the transaction, involve risks and uncertainties that may cause results to differ materially from those set forth in the statements. No forward-looking statement can be guaranteed, and actual results may differ materially from those projected. Medco and Express Scripts undertake no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise. Forward-looking statements are not historical facts, but rather are based on current expectations, estimates, assumptions and projections about the business and future financial results of the pharmacy benefit management and specialty pharmacy industries, and other legal, regulatory and economic developments. We use words such as “anticipates,” “believes,” “plans,” “expects,” “projects,” “future,” “intends,” “may,” “will,” “should,” “could,” “estimates,” “predicts,” “potential,” “continue,” “guidance” and similar expressions to identify these forward-looking statements. Actual results could differ materially from the results contemplated by these forward-looking statements due to a number of factors, including, but not limited to, the possibility that (1) Medco and Express Scripts may be unable to obtain stockholder or regulatory approvals required for the merger or may be required to accept conditions that could reduce the anticipated benefits of the merger as a condition to obtaining regulatory approvals; (2) the length of time necessary to consummate the proposed merger may be longer than anticipated; (3) problems may arise in successfully integrating the businesses of Medco and Express Scripts; (4) the proposed merger may involve unexpected costs; (5) the businesses may suffer as a result of uncertainty surrounding the proposed merger; and (6) the industry may be subject to future risks that are described in SEC reports filed by Medco and Express Scripts.

The foregoing list of factors is not exhaustive. You should carefully consider the foregoing factors and the other risks and uncertainties that affect the businesses of Medco and Express Scripts described in their respective Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and other documents filed from time to time with the Securities and Exchange Commission.

Additional Information and Where to Find It

In connection with the proposed merger, Express Scripts, Inc. will file with the SEC a registration statement on Form S-4 that will include a joint proxy statement of Medco and Express Scripts, and a prospectus of Express Scripts, as well as other relevant documents concerning the proposed merger. Stockholders are urged to read the registration statement and the proxy statement/prospectus contained therein regarding the merger when they become available and any other relevant documents as well as any amendments or supplements to those documents, because they will contain important information.

You will be able to obtain a free copy of the proxy statement/prospectus, as well as other filings containing information about Medco and Express Scripts, at the SEC’s Internet site (http://www.sec.gov). You will also be able to obtain these documents, free of charge, in the Investor Relations portion of the Medco website at http://www.medcohealth.com under the heading “Investors” and then under “SEC Filings.” Copies of the proxy statement/prospectus and the SEC filings that will be incorporated by reference in the proxy statement/prospectus can also be obtained, free of charge, by directing a request to Investor Relations, 100 Parsons Pond Drive, Franklin Lakes, NJ, 07417, 201-269-3400.

Participants in Solicitation

Medco and Express Scripts and their respective directors and executive officers may be deemed to be participants in the solicitation of proxies from the stockholders of Medco in connection with the proposed merger. Information about the directors and executive officers of Medco and their ownership of Medco common stock is set forth in the proxy statement for the Medco 2011 annual meeting of stockholders, as filed with the SEC on Schedule 14A on April 8, 2011. Information about the directors and executive officers of Express Scripts and their ownership of Express Scripts common stock is set forth in the proxy statement for the Express Scripts’ 2011 annual meeting of stockholders, as filed with the SEC on Schedule 14A on March 21, 2011. Additional information regarding the interests of those persons and other persons who may be deemed participants in the merger may be obtained by reading the proxy statement/prospectus regarding the proposed merger when it becomes available. You may obtain free copies of this document as described in the preceding paragraph.