Incorporating the Scientific Outlook on Development into the guiding ideology is the biggest highlight of a new amendment to the Constitution of the Communist Party of China (CPC), a spokesman said Sunday.

It is also the most prominent historic contribution in revising the Party's Constitution, said the spokesman with the secretariat of the 18th CPC National Congress.

The national congress Wednesday passed the Party Constitution amendment which has incorporated the Scientific Outlook on Development into the CPC guiding ideology, along with Marxism-Leninism, the Mao Zedong Thought, the Deng Xiaoping Theory and the important though of Three Represents.

The Scientific Outlook on Development was created by integrating Marxism with realities of modern China and with underlying features of the times, the spokesman said.

The theory has enriched and developed Marxism in development doctrine, and it also improved understanding on rules of human society development, socialist construction and governance, the spokesman said.

The Scientific Outlook on Development was added to the CPC Constitution at the 17th CPC National Congress in 2007. The spokesman said the theory became more meaningful and effective through practice and development in the past five years.

Party organizations in all localities and government departments unanimously agreed to incorporate it into the Party guiding ideology at the 18th national congress, the spokesman said.