Exhibit 10.50

GUARANTY

This GUARANTY (as amended, restated, supplemented, or otherwise modified and in effect from time to time, this “ Guaranty ”) is made as of this 31 ^st day of October, 2007, jointly and severally, by each of Averion, Inc., a Delaware corporation (“Averion Inc.”) and IT&E International, a California corporation (“IT&E,” and together with Averion Inc. and each other person or entity who becomes a party to this Guaranty by execution of a joinder in the form of Exhibit A attached hereto, is referred to individually as a “Guarantor” and collectively as the “ Guarantors ”) in favor of Cumulus Investors, LLC, a Nevada limited liability company, on its own behalf and in its capacity as collateral agent (together with its successors and assigns in such capacity, the “ Collateral Agent ”) for the benefit of the Buyers (as defined in the Purchase Agreement described below).

W I T N E S S E T H:

WHEREAS, as of the date hereof, Buyers have made certain financial accommodations to AVERION INTERNATIONAL CORP. , a Delaware corporation (the “ Company ”) and purchased certain secured senior notes in an original aggregate principal amount of up to $26,000,000 (such notes, together with any promissory notes or other securities issued in exchange or substitution therefor or replacement thereof, as any of the same may be amended, supplemented, restated or modified and in effect from time to time, the “ Notes ”);

WHEREAS, the Notes are being acquired by Buyers pursuant to a Securities Purchase Agreement dated as of October 31, 2007 among the Buyers and the Company (as the same may be amended, restated, supplemented or otherwise modified from time to time, the “ Purchase Agreement ”);

WHEREAS, pursuant to a Pledge Agreement of even date herewith (as the same may be amended, restated, supplemented or otherwise modified and in effect from time to time, the “ Company Pledge Agreement ”) by the Company in favor of the Collateral Agent, the Company has pledged and granted a lien on and security interest in all of the capital stock and other equity interests of each of Averion Inc. and IT&E to Collateral Agent, for its benefit and the benefit of the Buyers;

WHEREAS, pursuant to a Security Agreement of even date herewith (as the same may be amended, restated, supplemented or otherwise modified and in effect from time to time, the “ Security Agreement ”) by the “ Debtors ” (as defined therein), in favor of the Collateral Agent, each of the Debtors (including the Company and the Guarantors) has granted the Collateral Agent, for its benefit and the benefit of the Buyers, a first priority security interest in, lien upon and pledge of each of its rights in the Collateral (as defined in the Security Agreement); and

WHEREAS, the Guarantors are direct or indirect subsidiaries of the Company and, as such, will derive substantial benefit and advantage from the financial accommodations available to the Company set forth in the Purchase Agreement, the Notes and the other Transaction Documents, and it will be to each Guarantor’s direct interest and economic benefit to assist the Company in procuring said financial accommodations from Buyers.

NOW, THEREFORE , for and in consideration of the premises and in order to induce Buyers to purchase the notes and make the financial accommodations contemplated by the Purchase Agreement, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, each Guarantor hereby jointly and severally agrees as follows:

1.                                        Definitions :  Capitalized terms used herein without definition and defined in the Purchase Agreement are used herein as defined therein. In addition, as used herein:

“ Bankruptcy Code ” shall mean the Federal Bankruptcy Reform Act of 1978 (11 U.S.C. §101, et seq .), as amended and in effect from time to time thereunder.

“ Event of Default ” shall have the meaning ascribed to such term in the Notes.

“ Obligations ” shall mean (i) all obligations, liabilities and indebtedness of every nature of the Company from time to time owed or owing to the Buyers and Collateral Agent, including, without limitation, all obligations, liabilities and indebtedness of every nature of the Company under the Security Documents, the Purchase Agreement, the Notes, the Registration Rights Agreement and the other Transaction Documents, including, without limitation, the principal amount of all debts, claims and indebtedness, accrued and unpaid interest and all fees, taxes, indemnities, costs and expenses, whether primary, secondary, direct, contingent, fixed or otherwise, heretofore, now and/or from time to time hereafter owing, due or payable whether before or after the filing of a bankruptcy, insolvency or similar proceeding under applicable federal, state, foreign or other law and whether or not an allowed claim in any such proceeding, and (ii) all obligations, liabilities and indebtedness of every nature of the Guarantors from time to time owed or owing to the Buyers and/or Collateral Agent, including, without limitation, all obligations, liabilities and indebtedness of every nature of the Guarantors under or in respect of this Guaranty, the Security Documents, the Purchase Agreement, the Notes, the Registration Rights Agreement and the other Transaction Documents, as the case may be, including, without limitation, the principal amount of all debts, claims and indebtedness, accrued and unpaid interest and all fees, taxes, indemnities, costs and expenses, whether primary, secondary, direct, contingent, fixed or otherwise, heretofore, now and/or from time to time hereafter owing, due or payable whether before or after the filing of a bankruptcy, insolvency or similar proceeding under applicable federal, state, foreign or other law and whether or not an allowed claim in any such proceeding.

2.                                        Guaranty of Payment .

(a)                                   Each Guarantor, jointly and severally, hereby unconditionally and irrevocably guaranties (as primary obligor and not merely as a surety) the full and prompt payment and performance to Buyers and Collateral Agent, on behalf of itself and in its capacity as collateral agent for the benefit of Buyers, when due, upon demand, at maturity or by reason of acceleration or otherwise and at all times thereafter, of any and all of the Obligations.

(b)                                  Each Guarantor acknowledges that valuable consideration supports this Guaranty, including, without limitation, the consideration set forth in the recitals above, as well as any commitment to lend, extension of credit or other financial accommodation, whether

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heretofore or hereafter made by Buyers to the Company; any extension, renewal or replacement of any of the Obligations; any forbearance with respect to any of the Obligations or otherwise; any cancellation of an existing guaranty; any purchase of any of the Company’s assets by any Buyer or Collateral Agent; or any other valuable consideration.

(c)                                   Each Guarantor agrees that all payments under this Guaranty shall be made in United States currency and in the same manner as provided for the Obligations.

(d)                                  Notwithstanding any provision of this Guaranty to the contrary, it is intended that this Guaranty, and any interests, liens and security interests granted by any Guarantor as security for this Guaranty, not constitute a “Fraudulent Conveyance” (as defined below) in the event that this Guaranty or such interest is subject to the Bankruptcy Code or any applicable fraudulent conveyance or fraudulent transfer law or similar law of any state. Consequently, Guarantors, Collateral Agent and Buyers agree that if this Guaranty, or any such interests, liens or security interests securing this Guaranty, would, but for the application of this sentence, constitute a Fraudulent Conveyance, this Guaranty and each such lien and security interest shall be valid and enforceable only to the maximum extent that would not cause this Guaranty or such interest, lien or security interest to constitute a Fraudulent Conveyance, and this Guaranty shall automatically be deemed to have been amended accordingly at all relevant times. For purposes hereof, “ Fraudulent Conveyance ” means a fraudulent conveyance under Section 548 of the Bankruptcy Code or a fraudulent conveyance or fraudulent transfer under the provisions of any applicable fraudulent conveyance or fraudulent transfer law or similar law of any state, as in effect from time to time.

3.                                        Costs and Expenses . Each Guarantor, jointly and severally, agrees to pay on demand, all reasonable costs and expenses of every kind incurred by any Buyer or Collateral Agent: (a) in enforcing this Guaranty, (b) in collecting any of the Obligations from the Company or any Guarantor, and (c) in realizing upon or protecting or preserving any collateral for this Guaranty or for payment of any of the Obligations. “ Costs and expenses ” as used in the preceding sentence shall include, without limitation, reasonable attorneys’ fees incurred by any Buyer or Collateral Agent in retaining counsel for advice, suit, appeal, any insolvency or other proceedings under the Bankruptcy Code or otherwise, or for any purpose specified in the preceding sentence.

4.                                        Nature of Guaranty: Continuing, Absolute and Unconditional .

(a)                                   This Guaranty is and is intended to be a continuing guaranty of payment of the Obligations, and not of collectibility, and is intended to be independent of and in addition to any other guaranty, indorsement, collateral or other agreement held by Buyers or Collateral Agent therefor or with respect thereto, whether or not furnished by a Guarantor. None of Buyers and Collateral Agent shall be required to prosecute collection, enforcement or other remedies against Company, any other Guarantor or guarantor of the Obligations or any other person or entity, or to enforce or resort to any of the Collateral or other rights or remedies pertaining thereto, before calling on a Guarantor for payment. The obligations of each Guarantor to repay the Obligations hereunder shall be unconditional. Each Guarantor shall have no right of subrogation with respect to any payments made by any Guarantor hereunder until the termination of this Guaranty in accordance with Section 8 below, and hereby waives any benefit of, and any

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right to participate in, any security or collateral given to Buyers to secure payment of the Obligations, and each Guarantor agrees that it will not take any action to enforce any obligations of the Company to any Guarantor prior to the Obligations being finally and irrevocably paid in full in cash, provided that, in the event of the bankruptcy or insolvency of the Company, Collateral Agent, for the benefit of itself and Buyers, and Buyers shall be entitled notwithstanding the foregoing, to file in the name of any Guarantor or in its own name a claim for any and all indebtedness owing to a Guarantor by the Company (exclusive of this Guaranty), vote such claim and to apply the proceeds of any such claim to the Obligations.

(b)                                  For the further security of Buyers and without in any way diminishing the liability of the Guarantors, following the occurrence and during the continuance of an Event of Default, all debts and liabilities, present or future of the Company to the Guarantors and all monies received from the Company or for its account by the Guarantors in respect thereof shall be received in trust for Buyers and Collateral Agent and forthwith upon receipt shall be paid over to Collateral Agent, for its benefit and in its capacity as collateral agent for the benefit of Buyers, until all of the Obligations have been finally and irrevocably paid in full in cash. This assignment and postponement is independent of and severable from this Guaranty and shall remain in full effect whether or not any Guarantor is liable for any amount under this Guaranty.

(c)                                   This Guaranty is absolute and unconditional and shall not be changed or affected by any representation, oral agreement, act or thing whatsoever, except as herein provided. This Guaranty is intended by the Guarantors to be the final, complete and exclusive expression of the guaranty agreement between the Guarantors and Buyers. No modification or amendment of any provision of this Guaranty shall be effective against any party hereto unless in writing and signed by a duly authorized officer of such party.

(d)                                  Each Guarantor hereby releases the Company from all, and agrees not to assert or enforce (whether by or in a legal or equitable proceeding or otherwise) any “claims” (as defined in Section 101(5) of the Bankruptcy Code), whether arising under any law, ordinance, rule, regulation, order, policy or other requirement of any domestic or foreign government or any instrumentality or agency thereof, having jurisdiction over the conduct of its business or assets or otherwise, to which the Guarantors are or would at any time be entitled by virtue of its obligations hereunder, any payment made pursuant hereto or the exercise by any Buyer or Collateral Agent of its rights with respect to the Collateral, including any such claims to which such Guarantors may be entitled as a result of any right of subrogation, exoneration or reimbursement.

5.                                        Certain Rights and Obligations .

(a)                                   Each Guarantor acknowledges and agrees that Buyers and Collateral Agent, for its benefit and as collateral agent for the benefit of Buyers, may, without notice, demand or any reservation of rights against such Guarantor and without affecting such Guarantor’s obligations hereunder, from time to time:

(i)                                      renew, extend, increase, accelerate or otherwise change the time for payment of, the terms of or the interest on the Obligations or any part thereof or grant other indulgences to the Company or others;

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(ii)                                   accept from any person or entity and hold collateral for the payment of the Obligations or any part thereof, and modify, exchange, enforce or refrain from enforcing, or release, compromise, settle, waive, subordinate or surrender, with or without consideration, such collateral or any part thereof;

(iii)                                accept and hold any indorsement or guaranty of payment of the Obligations or any part thereof, and discharge, release or substitute any such obligation of any such indorser or guarantor, or discharge, release or compromise any Guarantor, or any other person or entity who has given any security interest in any collateral as security for the payment of the Obligations or any part thereof, or any other person or entity in any way obligated to pay the Obligations or any part thereof, and enforce or refrain from enforcing, or compromise or modify, the terms of any obligation of any such indorser, guarantor, or person or entity;

(iv)                               dispose of any and all collateral securing the Obligations in any manner as the Collateral Agent, in its sole discretion, may deem appropriate, and direct the order or manner of such disposition and the enforcement of any and all endorsements and guaranties relating to the Obligations or any part thereof as Collateral Agent in its sole discretion may determine;

(v)                                  (a) sell, exchange, enforce, waive, substitute, liquidate, terminate, release, abandon, fail to perfect, subordinate, accept, substitute, surrender, exchange, affect, impair or otherwise alter or release any collateral for any Obligation or any other guaranty therefor in any manner, (b) receive, take and hold additional collateral to secure any Obligation, (c) add, release or substitute any one or more other Guarantors, makers or endorsers of any Obligation or any part thereof and (d) otherwise deal in any manner with the Company and any other Guarantor, maker or endorser of any Obligation or any part thereof;

(vi)                               settle, release, compromise, collect or otherwise liquidate the Obligations;

(vii)                            determine the manner, amount and time of application of payments and credits, if any, to be made on all or any part of any component or components of the Obligations (whether principal, interest, fees, costs, and expenses, or otherwise), including, without limitation, the application of payments received from any source to the payment of indebtedness other than the Obligations even though Buyers might lawfully have elected to apply such payments to the Obligations to amounts which are not covered by this Guaranty;

(viii)                         take advantage or refrain from taking advantage of any security or accept or make or refrain from accepting or making any compositions or arrangements when and in such manner as Collateral Age