Many Global Problems Are Now Arbitrated by International Organizations 

The well-being of mankind, its peace and security, are unattainable unless and until its unity is firmly established.

(Gleanings from the Writings of Baha'u'llah, p. 286)

In cycles gone by, though harmony was established, yet, owing to the absence of means, the unity of all mankind could not have been achieved. Continents remained widely divided, nay even among the peoples of one and the same continent association and interchange of thought were wellnigh impossible. Consequently intercourse, understanding and unity amongst all the peoples and kindreds of the earth were unattainable. In this day, however, means of communication have multiplied, and the five continents of the earth have virtually merged into one. And for everyone it is now easy to travel to any land, to associate and exchange views with its peoples, and to become familiar, through publications, with the conditions, the religious beliefs and the thoughts of all men. In like manner all the members of the human family, whether peoples or governments, cities or villages, have become increasingly interdependent. For none is self-sufficiency any longer possible, inasmuch as political ties unite all peoples and nations, and the bonds of trade and industry, of agriculture and education, are being strengthened every day. Hence the unity of all mankind can in this day be achieved. Verily this is none other but one of the wonders of this wondrous age, this glorious century. Of this past ages have been deprived, for this century -- the century of light -- hath been endowed with unique and unprecedented glory, power and illumination. Hence the miraculous unfolding of a fresh marvel every day. Eventually it will be seen how bright its candles will burn in the assemblage of man. (Selections from the Writings of Abdu'l-Baha, p. 31)

 In 2005, there were 7,350 inter-governmental organizations and 51,509 non-governmental organizations for a total of 58,859. [Table 2.1 in Non-State Actors by Bob Reinalda]

See the Wikipedia page on International non-governmental organization.

See The Conference of NGOs in Consultative Relationship with the United Nations. The full members listing is here.