Mr Sendanayake started his career as an English Specialist trained teacher. 

Later,  he contributed to the field of English by working as an In-service advisor of English. 

Mr Sendanayake rendered his service in Sri Lanka Principal Service (SLPS) and Sri Lanka Education Administrative Service (SLEAS). He worked as the Deputy Director of Education (English & Foreign Languages) in the Central Province. He worked as the Coordinator of the Global School Partnership & Connecting Classrooms project with UK schools, under British Council.

After school education, Mr Sendanayake received the training of professional Education Development in the UK (Manchester). He has followed a number of English language training courses locally & Globally. In addition to the teacher training, he is currently working as a National trainer & Lecturer of Practical Psychology & Personal Development.