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                                                                 EXHIBIT 4

                              EMPLOYMENT AGREEMENT


         THIS AGREEMENT dated as of this fourth day of June, 1999 is made by
and among JEVIC TRANSPORTATION, INC., a New Jersey corporation (the "Company"),
YELLOW CORPORATION, a Delaware corporation ("Yellow"), and Joseph A. Librizzi,
(the "Executive").

         WHEREAS, Yellow and the Company are currently engaged in the
negotiation of an Agreement and Plan of Merger (the "Purchase Agreement")
pursuant to which Yellow would, through an indirect wholly owned subsidiary,
acquire all the shares of common stock of the Company; and

         WHEREAS, the Boards of Directors of the Company and Yellow have
approved the employment of the Executive on the terms and conditions set forth
in this Agreement; and

         WHEREAS, the Executive is willing, for the considerations provided, to
continue in the employment of the Company on the terms and conditions set forth
in this Agreement;

         NOW, THEREFORE, the parties hereto, intending to be legally bound,
agree as follows:

         1.      Employment. The Company hereby agrees to continue to employ

            the Executive, and the Executive hereby accepts such continued
            employment, upon the terms and conditions set forth in this
            Agreement. On and after the effective date of the merger of the
            "Purchaser" (as defined in the Purchase Agreement) into the Company
            contemplated by the Purchase Agreement (the "Merger Date"), Yellow
            shall cause the "Surviving Corporation" as defined in the Purchase
            Agreement to satisfy the Company's obligations under this Agreement;
            provided, however, that Yellow shall have no obligations or
            liabilities under this Agreement unless and until the Effective Date
            (as defined below) occurs. On and after the Merger Date, said
            Surviving Corporation shall be the "Company" for purposes of this
            Agreement.

         2.      Term. This Agreement shall become effective on, and the term
            (the "Term") of the Executive's employment under this Agreement
            shall commence on, the date on which the Purchaser purchases shares
            of the Company's stock pursuant to a tender offer (the "Effective
            Date") and shall continue until the date of termination of the
            Executive's employment with the Company.

         3.      Position and Duties. During the Term, the Executive shall
            serve as Senior Vice President - Marketing and Sales of the
            Company, and shall have such responsibilities and authority as is
            commensurate with such office. The Executive shall devote
            substantially all of his working time and efforts to the business
            and affairs of the Company.



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         4.      Compensation. During the Term, the Company shall provide the
            Executive with the following compensation and other benefits:

            (a)       Base Salary. The Company shall pay the Executive base
                 salary at the initial rate of $154,200 per annum, which shall
                 be payable in accordance with the standard payroll practices
                 of the Company. At no time during the Term shall the
                 Executive's base salary be decreased from the rate then in
                 effect except with the written consent of the Executive.

            (b)       Bonus. During the Term, the Executive shall participate
                 in the annual bonus program maintained for the executive
                 officers of the Company. The Executive's target bonus for each
                 fiscal year during the Term shall be no less than 30% of his
                 annual base salary for that year.

            (c)       Other Company, Benefits. During the Term, the Executive
                 shall be entitled to participate in, and to receive benefits
                 under, the benefit plans and programs that are at the
                 applicable time available to executives of the Company
                 generally and on terms and conditions that are no less
                 favorable than those applicable to executives of the Company
                 generally.

            (d)       Stock Options. As of the Effective Date, Yellow shall
                 grant to the Executive an option to purchase 20,000 shares of
                 common stock of Yellow with the following principal terms: (i)
                 an exercise price equal to the closing price of Yellow common
                 stock as reported by NASDAQ on June 4, 1999, (ii) vesting and
                 becoming exercisable at the rate of 25% on the first
                 anniversary of the Effective Date, 25% on the second
                 anniversary, 25% on the third anniversary, and the remaining
                 25% on the fourth anniversary, and (iii) other terms and
                 conditions substantially similar to stock options granted to
                 executives generally under Yellow's 1996 Stock Option Plan.
                 With respect to calendar years beginning after the Effective
                 Date, the Executive during the Term shall participate in
                 Yellow's stock option plans on terms and conditions
                 substantially similar to those generally applicable to
                 executives of Yellow and its subsidiaries.

            (e)       Perquisites. On and after the Effective Date, Yellow
                 shall cause the Company during the Term to provide to the
                 Executive the perquisites listed in Appendix A hereto.



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         5.      Right to Terminate Employment. The Company reserves the right
            to terminate the Executive's employment hereunder at any time,
            subject, however, to the termination procedures set forth in
            Section 7 of the Amended and Restated Severance Agreement dated as
            of June 4, 1999 between the Company and the Executive (the
            "Severance Agreement")to the extent such procedures are then
            applicable pursuant to the terms of the Severance Agreement. The
            Executive reserves the right to resign from employment with the
            Company at any time, subject, however, to any limitations on such
            right that may then be applicable pursuant to the terms of the
            Severance Agreement.

         6.      Relationship of this Agreement to Severance Agreement. Nothing
            in this Agreement shall affect in any way the rights and
            obligations of the Company and the Executive under the Severance
            Agreement, except that the Executive hereby agrees to the following
            modifications of the Severance Agreement, effective as of the
            Effective Date:

         (i)     an act or failure to act constituting "Good Reason" as
            described in subsection (i) of Section 15 (M) of the Severance
            Agreement shall not be deemed to occur on or after the Effective
            Date so long as the Executive has the title, responsibilities and
            authority set forth in Section 3 of this Agreement (notwithstanding
            changes in the Executive's status, responsibilities and authority
            resulting from the Company's ceasing to be a separate public
            company), and

         (ii)    an act or failure to act constituting "Good Reason" as
            described in subsection (v) or (vi) of Section 15 (M) of the
            Severance Agreement shall not be deemed to occur by reason of the
            cessation of the Executive's participation in the Company's stock
            option and other stock-based plans so long as Yellow complies with
            Section 4 (d) of this Agreement on and after the Effective Date,
            and

         (iii)   an act or failure to act constituting "Good Reason" as
            described in subsection (v) or (vi) of Section 15(M) of the
            Severance Agreement shall not be deemed to occur by reason of the
            limitation of the Executive's target bonus to the level provided
            for in Section 4 (b) of this Agreement, and

         (iv)    an act or failure to act constituting "Good Reason" as
            described in subsection (v) or (vi) of Section 15 (M) of the
            Severance Agreement shall not be deemed to occur by reason of the
            elimination or modification of any perquisites or fringe benefits
            enjoyed by the Executive before the Effective Date (other than
            benefits under any Company "employee benefit plan" as defined in
            Section 3 (3) of the Employee Retirement Income Security Act of
            1974, as amended) so long as the Company provides the perquisites
            set forth in Appendix A hereto, and



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         (v)     Yellow's execution of this Agreement shall be deemed to fully
            satisfy the Company's obligations pursuant to Section 9.1 of the
            Severance Agreement.

         7.      Miscellaneous. No provision of this Agreement may be modified,
            waived or discharged unless such waiver, modification or discharge
            is agreed to in writing and signed by the party against whom such
            waiver, modification or discharge is sought to be enforced (with
            such signature, in the case of the Company or Yellow, to be made by
            a duly authorized officer thereof). No waiver by any party hereto
            at any time of any breach by any other party hereto of, or
            compliance with, any condition or provision of this Agreement to be
            performed by such other party shall be deemed a waiver of similar
            or dissimilar provisions or conditions at the same or at any prior
            or subsequent time. No agreements or representations, oral or
            otherwise, express or implied, with respect to the subject matter
            hereof have been made by any party which are not expressly set
            forth in this Agreement. The validity, interpretation, and
            construction of this Agreement shall be governed by the laws of the
            State of New Jersey. Payments provided for hereunder shall be paid
            net of withholding required under federal, state or local law and
            any additional withholding to which the Executive has agreed.

            IN WITNESS WHEREOF, this Agreement has been executed, as of the
            date first written, on behalf of the Company by its duly authorized
            officer, on behalf of Yellow by its duly authorized officer, and by
            the Executive.

                                               JEVIC TRANSPORTATION, INC

/s/ Karen B. Muhlschlegel              By: /s/ Harry J. Muhlschlegel
- -----------------------------------        -------------------------------------
Secretary

                                                   YELLOW CORPORATION

/s/ William F. Martin, Jr.             By: /s/ H.A. Trucksess III
- -----------------------------------        -------------------------------------
Secretary

                                                        EXECUTIVE

                                       By: /s/ Joseph A. Librizzi
                                           -------------------------------------



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                                   APPENDIX A


         Under Section 4 (e) of the Employment Agreement between the Executive,
Jevic Transportation, Inc. and Yellow Corporation the following perquisites
shall be provided:

         (A)     Car Allowance. Executive shall be provided a car or car
            allowance at least equal to that provided under Jevic
            Transportation, Inc.'s policy dated March 5, 1996.

         (B)     Vacation. Executive will be entitled to annual vacation at
            least equal to that currently provided as an employee of Jevic
            Transportation under their current policy and practice.

         (C)     Supplemental Retirement Plan. Continued eligibility to
            participate in Jevic Transportation's non-qualified supplemental
            retirement arrangements through Fidelity Investments.

         (D)     Split Dollar Life Insurance. Continued participation in the
            Split Dollar Life Insurance Program currently provided as an
            Executive of Jevic.

         (E)     Financial Planning / Tax Preparation. Executive will be
            entitled to an annual reimbursement of expenses in conjunction with
            personal financial planning and/or income tax return preparation
            not to exceed $1,500.

         (F)     Executive Physical. Executive will be reimbursed up to $350
            annually for expenses in conjunction with a physical examination.
            This benefit shall be in addition to any amounts otherwise payable
            under Jevic's Medical Benefit Plan.