Len has decades of experience helping clients solve tax and estate planning challenges so they can build their wealth and bequeath it to younger generations. He serves as Partner and Chair of the Private Client Services Department at Wiggin and Dana. Len advises clients on estate and probate law, tax planning, elder law, and family business succession planning.

Len is a nationally recognized trust and estate lawyer. Worth Magazine has named him one of "Top 100 Trust and Estate Lawyers" in the country. Chambers High Net Worth recognized Len in 2018. He was also recognized in the 2018 edition of New York Best Lawyers listing, as he has been since 2008. Connecticut Super Lawyers magazine has listed him in the category of Estate and Probate since 2007 as well. 

Len is a prolific thought leader in his field. He is a contributing writer on estate planning to several law publications, and is a frequent speaker on estate and tax planning topics to bar associations, business groups, and continuing education programs. He presents at an annual fiduciary income tax workshop for Professional Education Systems. He prepared a review of new developments in estate and gift taxation published in The Tax Lawyer. He co-authored an article on "Creative Clients Require Creative Planning" in the Connecticut Law Tribune, which was selected by the Legal Times for national publication. He also authored "Excluded Gifts Are Not Necessarily GST-Exempt" for Probate & Property Magazine.

Len is a member of the Taxation Section, the Generation Skipping Trusts Committee of the Estate Planning and Drafting Group of the Real Property, Probate and Trust Law Section of the American Bar Association, and was Chairman of a Task Force on Charitable Easements. He is also a member of the Trusts and Estates Section of the New York State Bar Association and the Executive Committee of the Estates and Probate Section of the Connecticut Bar Association.