The objective of this chapter is to introduce the section-wise sinonasal anatomy. Coronal sections form the basic imaging plane for evaluating the paranasal sinuses and nasal cavity. Similarly bone window is the most informative window setting. This chapter depicts the sectional anatomy in all three planes through sequential images. Coronal scans well depict the nasal turbinates and meati, nasal septum, agger nasi (AN) cell, various sinuses, components of ostiomeatal unit and adjacent skull base. Consecutive sagittal sections are depicted from lateral to medial. Sagittal sections well depict the drainage pathways of frontal sinus and sphenoid sinus.