1. Introduction 1.1. Nature of rock 1.2. Damage and acoustic emission (AE) 1.3. Basic concepts of AE 2.

Monitoring AE 2.1. Laboratory studies 2.1.1. AE sensor, pre-amplifier 2.1.2.

Electric noise and filters 2.2 Field studies 2.2.1. Sampling time and monitoring frequency 2.2.2. Attenuation and resolution of amplitude 2.

3 AE waveform 2.3.1. Trigger time, duration, and maximum amplitude 2.3.2. Frequency analysis 2.3.

3. AE count rate 2.4. Application: stress measurement and Kaiser effect 3. Source location of AE 3.1. Problem statement and direct method 3.2.

Lattice approach: trial-and-error method 3.3. Iterative approach: least squares method 3.4. Special cases Method of source location under a 3.4.1. P-wave anisotropy 3.

4.2. Constraint condition 3.4.3. P- and S-wave arrival times 3.4.4.

Propagation paths and sensor positions 3.5. Application: fracture initiation 4. Source mechanism of AE 4.1. Mechanics of microcracking 4.2. Fault plane solution and stereographic projection 4.

3. Moment tensor analysis 4.3.1. Displacement discontinuity model 4.3.1.2.

Sensor calibration 4.4. Application: shear banding 5. Rock mechanics issues 5.1. Hydraulic fracturing 5.1.1.

Laboratory experiments 5.1.2. Field studies 5.2. Hot dry rock geothermal project 5.3. In situ stress measurement 5.

4. Heater test 5.5. Underground powerhouse   6. Concluding remarks 6.1. Numerical modeling 6.2.

Structural health monitoring.