Nihal Sri Ameresekere was appointed, as a Member of the Company Law Advisory Commission, in July 2004 by the Minister of Trade & Commerce.

Ameresekere actively participated in realizing the mandate given to the Company Law Advisory Commission to finalise the formulation of a new Companies Act.

In actively participating in the formulation of the new Companies Act, Ameresekere also assisted the Commission in having discussions with political groups, to clarify the implications of the new provisions in the proposed statute, and to also accommodate their views.

Subsequently, the new Companies Act No. 7 of 2007 was gazetted on 19th May 2006, and was unanimously passed by the Parliament of Sri Lanka on a bi-partisan basis on 20th October 2006, and was enacted into law on 20th March 2007 with the certification by the Speaker of Parliament of Sri Lanka, and came into operation on 3rd May 2007, as per the Order gazetted in terms of Section 1(2) of the Companies Act No. 7 of 2007.  Having accomplished such task, Ameresekere resigned, as a Member of the Company Law Advisory Commission, at the end of May 2007.