The operative approaches to the 3rd ventricle are divided on the basis of whether they are suitable for reaching the anterior or posterior part of the 3rd ventricle. The approaches suitable for lesions within or compressing the anterior portion of the 3rd ventricle are the trans-sphenoidal, subfrontal, frontotemporal, subtemporal, anterior transcallosal, and anterior transventricular. The approaches suitable for reaching the posterior portion of the 3rd ventricle are the posterior transcallosal, posterior transventricular, occipital transtentcrial, and infratentorial supracerebellar. Considerations important in selecting one of these approaches are reviewed.