The invention includes methods of forming pluralities of electrically conductive structures. The methods can include formation of a gradient-containing material across a substrate and in direct physical contact with conductive surfaces of nodes. The gradient-containing material can consist essentially of tantalum nitride at a lowermost portion in contact with the conductive surfaces, consist essentially of tantalum at an uppermost portion, and have a TaN/Ta gradient extending between the lowermost and uppermost portions. Alternatively, the gradient-containing material can have a Co/W gradient extending therethrough. Conductive structures can be formed over the gradient-containing material. The invention also includes constructions comprising electrically conductive lines over a material having a TaN/Ta gradient, or a W/Co gradient, extending therethrough.