This chapter contains sections titled: Micro Heat Exchangers with Wide and Flat Channels Cross-Flow Heat Exchange in Stacked Plate Devices Cross-Flow Heat Exchange Based on Cross-Mixing Counter-Flow Heat Exchange in Stacked Plate Devices Electrically Heated Stacked Plate Devices Micro Heat Exchangers with Narrow and Deep Channels Heat Exchanger with One-Sided Structured Channels Heat Exchanger with Double-Sided Structured Channels Micro Heat Exchangers with Breakthrough Channels Axial Heat Conduction Numerical Calculations of the Influence of Material Choice on Heat Transfer Efficiency The Use of Thermal Blocking Structures Permanent Generation of Entrance Flow by Fins Generation of a Periodic Flow Profile by Sine-Wave Microchannels Microtechnology-Based Chemical Heat Pumps Performance Characterization of Micro Heat Exchangers Temperature Profiles of Micro Heat Exchangers Yielded by Thermograms of Infrared Cameras