Exhibit 10.1

Letter of Agreement

Whereas, Mary A. Tremblay (the “Employee”) has served Lydall, Inc. (the “Company” or “Lydall”) for 18 years, in most recent years as Vice President, General Counsel and Corporate Secretary, but has expressed a desire to work reduced hours due to family obligations; and

Whereas, the Company values the experience and knowledge of the Employee and desires to retain the Employee,

Now therefore, this Letter of Agreement (“Agreement”) sets forth the understandings and agreements of the Employee and (the Company (hereinafter collectively referred to as the “Parties”) with respect to the part time legal counsel position which Employee will undertake for the two (2) year period commencing and effective upon a date agreed upon by the Company after the hiring of Lydall’s new General Counsel and expiring two (2) years thereafter.

1. The parties understand that while Employee will be performing legal services for Lydall for 20 hours per week on a mutually agreeable schedule, the remainder of her time may be spent independently in pursuits which shall not conflict with Lydall’s business in any manner.

2. At all times throughout the term of this Agreement, Employee will be considered a part time employee of Lydall eligible for such benefits as are afforded to other part time employees of the Company working 20 hours per week.

a. Lydall will provide Employee with an office and such office equipment and supplies as are necessary for her to perform her work.

b. The business expenses incurred by Employee will be reimbursed to her in accordance with Lydall’s normal policies and procedures.

c. Lydall will provide Employee, at no cost to Employee, professional liability (malpractice) insurance coverage under the “Employed Lawyers Professional Liability Policy” as has been provided for her benefit in the past.

d. Employee will have 4 weeks of unpaid vacation per contract year to be taken as mutually agreed by the Parties.

e. Employee will report to the General Counsel of Lydall who will assign Employee such work as General Counsel deems necessary and

appropriate in furtherance of Lydall’s business pursuits. Such work may require Employee to travel from time to time, which will be mutually agreeable times consistent with the requirements of the work to be performed.

3. Employee will accurately record all time spent performing work on behalf of Lydall in the Kronos system and include the date the