Saivism is one of the pervasive expressions of Indian Religious Culture stretching to the dim past of prehistory and surviving as a living force in the thought and life of millions of Hindus especially in Southern India and Northern Ceylon. The present work is a scholarly reconstruction of Saivism in its characteristic and classical form as Saiva Siddhanta, focusing mainly on the philosophical doctrine and presenting a conceptual analysis of its formative notions, problems and methods.