He clarified the philosophical principle that the revolutionary party is, in its essence, the party of its leader, a political organization that materializes the leader's idea and leadership.

Through the energetic ideological and theoretical activities, he formulated President Kim Il Sung's revolutionary idea as Kimilsungism, the guiding idea of the Workers' Party of Korea, and thus provided a firm guarantee for strengthening the WPK into the party of the President.

In the period of the Arduous March, the forced march when the country was in hard time, Kim Jong Il gave fullest play to the role of the WPK as the organizer and leader of all victories of the Korean people and wisely led the struggle for defending socialism to victory.

Highly conscious of his responsibility for accomplishing the global independence, he wrote many celebrated works like "The Historical Lesson in Building Socialism and the General Line of Our Party", "Abuses of Socialism Are Intolerable" and "Socialism Is a Science", so as to clearly indicate the way out for the ruling parties in socialist countries.

The publication of his famous work "On the Fundamentals of Revolutionary Party Building" evoked a great sensation in over 100 countries.

Seminars, lectures and workshops on his works took place on a worldwide scale. And the progressive parties across the world put forward him as their honorary chairman.

Thanks to his outstanding ideology and seasoned leadership, the WPK could be developed into a model party while demonstrating its prestige and dignity the world over.

The undying feats performed by Kim Jong Il in party building is being creditably carried forward by supreme leader Kim Jong Un.