EXHIBIT 10.8

                          WAIVER OF NEGATIVE COVENANTS

The undersigned holder (the "Holder") of Variable Rate Convertible Debentures
due 2008 (the "Debentures") issued by Diomed Holdings, Inc. (the "Company") and
the Company hereby agree as follows:

In connection with the Company's proposed consummation of the purchase and sale
of the Company's Preferred Stock, par value $0.001 per share (the "Preferred
Stock") and Warrants (the "Investor Warrants") to purchase Common Stock, par
value $0.001 of the Company ("Common Stock"), for aggregate gross proceeds of
approximately $10,000,000 to $12,000,000, on substantially the terms and
conditions described in the term sheet annexed hereto as Exhibit A, and as the
Company and the investors in the Financing shall agree in the definitive
Financing documentation (the "Financing"), the Holder hereby waives the negative
covenants set forth in Sections 7(c) and 7(d) of the Debenture as they pertain
to the Financing. For the avoidance of doubt, the foregoing waiver pertains to
the Financing only and not to any future financing or other transaction which
would be precluded by the negative covenants contained in the Debenture. All
other terms and conditions of the Debenture remain in full force and effect.

Notwithstanding anything herein to the contrary, the waiver granted by the
Holder hereunder shall only apply to the extent that the Company redeems
securities for no more than the actual cash received for the original purchase
of such securities by the purchaser in the Financing. This waiver shall not
apply to the payment to any person or entity of any amounts above what was
initially paid for such securities, including but not limited to the payment of
any default premiums, liquidated damages or late fees. Any redemption above the
original purchase price paid by a participant in the Financing, in cash or kind,
shall remain strictly prohibited by the terms of the Debentures. Notwithstanding
anything herein to the contrary, the participants in the Financing shall be
permitted to collect customary liquidated damages after the effective date of
their registration statement for periods during which the prospectus thereunder
is not available for the resale of the shares held by such participants.

As an inducement to the Holder to provide the foregoing waiver, and in
consideration therefor, the Company hereby agrees to issue, effective at the
time of consummation of the Financing, to the Holder warrants to purchase an
aggregate of up to __________ shares of Common Stock (the "Debenture Holder
Warrants") on the same terms and conditions as the Investor Warrants. For the
avoidance of doubt, the Debenture Holder Warrants shall only be issuable if the
Company completes the Financing.

Dated:  September 26, 2005
                        [NAME OF HOLDER]

                        By:  ___________________________________
                                (Signature of authorized person above)

                        Name:  _________________________________
                        Title:    _________________________________

                        DIOMED HOLDINGS, INC.

                        By:  ___________________________________
                        David Swank, Chief Financial Officer

                                                       NOTE: EXHIBIT A OMITTED
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