The efficient delivery with existing linac and MLC makes IMAT a practical choice.

Mechanical precision is superior for the gamma knife as compared with the linac.

The linac allows flexible, ready access to individualized beam control, without intrinsic field size limitations.

Treatment planning for the linac is not standardized, but existing systems are based on well-known algorithms.

Fixed-field intensity-modulated treatments, delivered by conventional linac-plus-multileaf systems, have rapidly become the most common form of IMRT.