SECURITIES AND EXCHANGE COMMISSION
                             Washington, D. C. 20549

                                    FORM 8-K

                                 Current Report

                     Pursuant To Section 13 or 14(d) of the
                         Securities Exchange Act of 1934

        Date of Report (Date of earliest event reported) November 9, 2004
                                                         ----------------

                            PSYCHEMEDICS CORPORATION
             ------------------------------------------------------
             (Exact Name of Registrant As Specified In Its Charter)

                                    DELAWARE
                            -------------------------
                 (State if Other Jurisdiction of Incorporation)

        1-13738                                         58-1701987     
    ---------------                                --------------------
(Commission File Number)                    (I.R.S. Employer Identification No.)

  125 Nagog Park, Acton, Massachusetts                          01720
----------------------------------------                        -----
(Address of Principal Executive Offices)                      (Zip Code)

                                 (978) 206-8220
                          -----------------------------
              (Registrant's Telephone Number, Including Area Code)

                                       N/A
                          -----------------------------
          (Former Name or Former Address, if Changed Since Last Report)



Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions (see General Instructions A.2. below):


[ ]  Written communications pursuant to Rule 425 under the Securities Act 
     (17 CFR 230.425)

[ ]  Soliciting material pursuant to Rule 14a-12 under the Exchange Act 
     (17 CFR 240.14a-12)

[ ]  Pre-commencement communications pursuant to Rule 14d-2(b) under the
     Exchange Act (17 CFR 240.14d-2(b))

[ ]  Pre-commencement communications pursuant to Rule 13e4(c) under the Exchange
     Act (17 CFR 240.13e-4(c))





ITEM 4.01.  CHANGES IN REGISTRANT'S CERTIFYING ACCOUNTANT.

(a)  Information required by Item 304(a)(1) of Regulation S-K.

    (i)   On November 9, 2004 the Audit Committee of the Registrant dismissed
          Ernst & Young LLP ("E&Y") as the Registrant's independent registered
          public accounting firm.

    (ii)  E&Y served as the Registrant's independent registered public
          accounting firm to audit the Registrant's two most recent fiscal year
          ends. The reports of E&Y on the financial statements of the Registrant
          at December 31, 2002 and December 31, 2003, and for each of the years
          ended December 31, 2003, did not contain an adverse opinion or
          disclaimer of opinion and were not qualified or modified as to
          uncertainty, audit scope or accounting principles.

    (iii) In connection with its audits for the two most recent fiscal years
          and through November 9, 2004, there have been no disagreements with
          E&Y on any matter of accounting principles or practices, financial
          statement disclosure, or auditing scope or procedure, which
          disagreements, if not resolved to the satisfaction of E&Y, would have
          caused E&Y to make reference to the matter in their report.

(b)  Information required by Item 304(a)(2) of Regulation S-K.

     (i)  On November 9, 2004 the Audit Committee of the Registrant engaged BDO
          Seidman LLP as the Registrant's independent registered public
          accounting firm.

     (ii) During Psychemedics Corporation's fiscal years ended December 31, 2002
          and 2003 and the subsequent interim period ended November 9, 2004, the
          Company did not consult with BDO Seidman LLP with respect to any of
          the matters described in Regulation S-K Item 304 (a)(2)(i) or (ii)).

(c)  Information required by Item 304(a)(3) of Regulation S-K.

     The Company has requested E&Y to furnish it a letter addressed to the
     Commission stating whether it agrees with the above statements. A copy of
     that letter dated November 12, 2004, is filed as Exhibit 16 to this Form
     8-K.

(d)  A copy of the press release announcing the appointment of BDO Seidman LLP 
     is filed as Exhibit 99 to this Form 8-K.



ITEM 9.01.  FINANCIAL STATEMENTS AND EXHIBITS.

(c)  Exhibits

EXHIBIT NO.       DESCRIPTION

   16             Letter from Ernst & Young LLP to the Securities and Exchange 
                  Commission dated November 12, 2004.

   99             Press release dated November 9, 2004





                                    SIGNATURE

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                     PSYCHEMEDICS CORPORATION
Dated: November 12, 2004


                                     By:  /s/ Peter C. Monson                   
                                        ----------------------------------------
                                        Peter C. Monson, Chief Financial Officer







                                  EXHIBIT INDEX

EXHIBIT NO.       DESCRIPTION

   16             Letter from Ernst & Young LLP to the Securities and Exchange 
                  Commission dated November 12, 2004.


   99             Press release dated November 9, 2004