Sison Reader Series Book 20, Proletarian Internationalism and International Solidarity consists of Jose Maria Sison's writings (essays, articles, speeches, messages, statements and interviews) on the subject of proletarian internationalism and international anti-imperialist solidarity. It highlights the role of international solidarity and practical cooperation in the advance of national liberation movements and proletariant revolution in countries, to raise the socialist cause around the world.

The rest of the book's content consists of messages and statements of proletarian internationalism, and solidarity and support to peoples and organizations in the struggle against imperialism and all reaction. They underscore the role of the proletariat in building revolutionary parties to develop and strengthen the revolution towards socialism among all oppressed nations and peoples.