Many warriors choose – or are forced – to undergo some form of augmentation work; a catch-all for a variety of procedures that interfere with the purity of the human form in an attempt to create better warriors. Such augmentation work can be broadly classified in five groups; also included are some examples of use.

Drugs: The simplest form is drug use. Ranging from the use of certain types of obscura to dull pain and make warriors 'brave', to advanced combat drugs such a the frenzon used on Penal Legion troopers. Space Marine power armour contains an extensive array of combat drugs that can be administered by auto-injectors.

Biochemical conditioning: Extensive and prolonged drug use aimed at making lasting changes in the body (most such treatments require indefinite maintenance as well, even after the desired effect has been achieved). One example is the prolonged use of certain herb mixtures on feral worlds that can make warriors semi-immune to pain . Another is a substance favoured by underhive gangers that makes human eyes able to see in near-total darkness. Space Marines undergo a heavy regiment of biochemical condition during their creation; to enhance their mental and physical faculties.

Biomechanical reconstruction: Invasive chirurgery that replace/add/modify parts of the human body. Advanced procedures use micro- or nanochirurgery. Biomechanical reconstruction can replicate many of the same effects as cybernetic enhancements; only they are biological not mechanical in nature. The additional organs carried by Space Marines are good examples.

Invasive geneering: A term for tailored viruses that are injected into the host body with a specific goal; to rewrite part of the targets gene structure. Only the Magi Biologis of the Mechanicus routinely perform such techno-arcane miracles, and even for them the procedure is difficult and fraught with danger (for the patient). Space Marines are created using invasive geneering.

Cybernetic enhancements: Cybernetic enhancements can replace damaged or destroyed flesh, or they can add new capabilities to the human body. Cybernetics range from crude systems of steel and chrome to hi-end components that are undistinguishable from flesh. The most important cybernetic enhancements are those that allow the human mind to interface with machine spirits; this is largely the province of the Adeptus Mechanicus, although Space Marines have a cranial/spinal implant that allow them to interface directly with the machine spirit inhabiting their suit of power armour. Other warriors sometimes employ lesser systems that allow them to interface with their weapons.