Abstract: An improved bricklayer's guide, and more particularly, a simplified and efficient adjustable support for the line used by masons as a guide for laying successive layers of bricks or blocks of various sizes. The bricklayer's guide or "line dog" consists of a combination of notched posts or standards that will cooperate in providing the desired width and a series of notches on one post that will engage an offset notch on a second post to provide the desired adjustment and secure the guide in place.