The rodent somatic sensory system is characterized by a prominent representation of the mystacial vibrissae, which form an orderly array of low-threshold mechanoreceptors. Centrally, the arrangement of the vibrissal pad is maintained in arrays of cellular aggregates referred to as barrelettes (brainstem), barreloids (thalamus), and barrels (primary sensory cortex). Trigeminal brainstem nuclei that receive vibrissal primary afferents give rise to two main streams of information, the lemniscal and paralemniscal pathways. The lemniscal pathway arises from the trigeminal nucleus principalis, transits through the ventral posterior medial nucleus of the thalamus, and projects to the primary somatosensory cortex. The paralemniscal pathway arises from the rostral part of trigeminal spinal nucleus interpolaris, transits through the posterior group of the thalamus, and projects to the somatosensory cortical areas and the vibrissa motor cortex. In this chapter, we review the anatomical organization of these pathways and propose that whereas the lemniscal pathway encodes both touch and whisking kinematics, the paralemniscal pathway signals the valence of orofacial inputs. Lastly, we call attention to the importance of understanding sensory processing in the brainstem trigeminal nuclei to understand their role in regulating behavior. These nuclei are richly interconnected and contain inhibitory circuits that operate both pre- and postsynaptically.