Selective attention relies on intricate neural mechanisms that govern how the brain processes information. In this lecture, I will explore research on the neural underpinnings of voluntary spatial, feature, and object attention, utilizing both EEG and fMRI techniques. I will highlight key findings related to attentional control in the frontal and parietal cortices, as well as how these processes influence sensory and perceptual processing. Additionally, I will present studies examining voluntary attention in free-choice conditions, where individuals exert their free will to direct attention without external guidance. The framework for this presentation is our Specificity of Control (SpoC) Model of attention, which highlights the microstructural organization of top-down control and the specificity of sensory biasing it imparts in the visual cortex.