Why do I need to gesso my support?
Think of gesso as the bridge between your support and your paint. Gesso is made to penetrate canvas and provide a "tooth" for the paint to adhere to. Products like GOLDEN Heavy Body Acrylics are too thick to effectively penetrate the canvas like gesso does, and you won't have as good adhesion. Gessoing also prepares the surface with an even coating for easier painting.

Is gesso the only product suitable for priming?
While GOLDEN White and Black Gessos are specifically made to be used as a primer, other products can work as well. GOLDEN High Load Acrylics are in a sense colored gessos. Instead of using the standard Titanium Dioxide Pigment, they are made with another pure pigment, such as Ultramarine Blue. The HLA's can be used to tint Gesso or mixed in any combination with each other to create a unique ground. They work quite well as as an underpainting, providing adequate tooth for any paints being applied over them.

I want to see the actual canvas while painting, does GOLDEN make a clear gesso?
GOLDEN does not have a product called Clear Gesso. However, GOLDEN Matte Medium and Fluid Matte Medium works quite well for this purpose. The matting solids provide enough tooth to be used as a primer and are thin enough to effectively penetrate the canvas.

I heard acrylic primers are not good for oil paints. Why not?
Many artists have expressed concern about acrylic gesso, primer and paint used under oil paints, because they react too differently to environmental changes such as temperature and humidity. Others argue acrylics are too slick of a surface for proper adhesion. GOLDEN Laboratories have yet to find a case of delamination due to the acrylics being under oils. However, we feel adequate adhesion and allowing coats to properly cure are essential between the two products, and if the acrylic product does not have a certain degree of roughness to it, then apply a thin coat of Matte Medium to provide tooth. The issue of differences in reactions of environment needs more verification, although the alternatives to acrylic sizing and priming layers (Hide Glues and PVA Glues) also react to environmental changes different than oils, often in a more extreme manner than acrylics.