In this capacity his industry and his talent speedily won for him a commanding position in the Estates of Holland, and he became one of the Prince of Orange's confidential friends and advisers.

In 1586 he was appointed Advocate of Holland in succession to Paul Buys.

This office included the duties of legal adviser, secretary and likewise in a sense that of "Speaker" to the Provincial Estates.

In addition to all this he was the mouthpiece in the States-General of the deputation representing the Provincial Estates, and exercised in that assembly all the authority attaching to the man who spoke in the name of Holland.

At this time of transition, by his predominance alike in his own province of Holland and in the States-General, he was able to secure for the general policy of the Union, especially in the conduct of foreign affairs, a continuity of aim and purpose that enabled the loosely-cemented and mutually jealous confederacy of petty sovereign states to tide-over successfully the critical years which followed the departure of Leicester, and to acquire a sense of national unity.
The brain and the diplomatic skill of the great statesman would, however, have been of little avail without the aid of the military abilities of Maurice of Nassau.