A system for thermal control of additive manufacturing, the system comprising: a build volume within which a part is additively manufactured; feedstock preparation apparatus configured to prepare a feedstock material such that the feedstock material bonds, fuses or otherwise joins to another section of the part comprising a primary heat source configured to heat a feedstock material such that the feedstock material bonds, fuses or otherwise joins to another section of the part; additionally to the feedstock preparation apparatus, an active heat source positioned relative to the build volume and configured to actively deliver heat to discrete sections of the part as the part is being additively manufactured; a thermal sensor positioned relative to the build volume and configured to acquire thermal data associated with the part as the part is being additively manufactured; and a controller operatively coupled to the active heat source and the thermal sensor and configured to direct delivery of heat from the active heat source to discrete sections of the part based at least in part on the thermal data as the part is being additively manufactured; and wherein: the active heat source comprises one or more of a laser and a lamp; and the system further comprises a support bed positioned relative to the build volume and configured to support the part as the part is being additively manufactured; the support bed is transparent to infrared light; and the active heat source is configured to actively deliver heat through the support bed to discrete sections of a lower surface of the part as the part is being additively manufactured. a build volume within which a part is additively manufactured; feedstock preparation apparatus configured to prepare a feedstock material such that the feedstock material bonds, fuses or otherwise joins to another section of the part comprising a primary heat source configured to heat a feedstock material such that the feedstock material bonds, fuses or otherwise joins to another section of the part; additionally to the feedstock preparation apparatus, an active heat source positioned relative to the build volume and configured to actively deliver heat to discrete sections of the part as the part is being additively manufactured; a thermal sensor positioned relative to the build volume and configured to acquire thermal data associated with the part as the part is being additively manufactured; and a controller operatively coupled to the active heat source and the thermal sensor and configured to direct delivery of heat from the active heat source to discrete sections of the part based at least in part on the thermal data as the part is being additively manufactured; and wherein: the active heat source comprises one or more of a laser and a lamp; and the system further comprises a support bed positioned relative to the build volume and configured to support the part as the part is being additively manufactured; the support bed is transparent to infrared light; and the active heat source is configured to actively deliver heat through the support bed to discrete sections of a lower surface of the part as the part is being additively manufactured.