This invention is directed to devices and methods for stereotactic access, and particularly to a frameless stereotactic access device for accessing a body cavity and methods therefor. In general, a stereotactic device may include portions or features for fixing the device to a portion of a patient's body, such as, for example, a skull, such that the device may be generally spatially fixed in relation to the patient's body or part thereof. The stereotactic device may also generally include portions or features for guiding a medical device or other device at a particular trajectory in relation to the patient's body or part thereof.