Once seen as a characteristic property of matter, spontaneous emission (SpE) results from the interaction between matter and the modes of the electromagnetic field. It can therefore be tailored to a large extent, as shown by S. Haroche and coworkers in the early 80’s, in pioneering cavity-quantum
electrodynamics (CQED) experiments realized with single atoms placed inside electromagnetic cavities. In spite of a tremendous potential interest, the implementation of CQED concepts in the field of optoelectronics has long been delayed, due to the lack of suitable solid-state emitters. In this context, the observation of atomic-like emission lines for single self-assembled quantum dots (QDs) in 1994 has given a strong stimulus to the development of solid-state CQED. After a brief overview of the early development of this field, I will present two strategies which provide a nearly perfect control of the emission of a QD, respectively based on SpE enhancement (Purcell effect) in optical microcavities and on SpE inhibition in photonic wires. Based on these advances, high-efficiency single-mode single photon sources (SPS) have been developed. SPS belong to a novel generation of quantum optoelectronic devices, which exploit CQED effects, and open wide perspectives for quantum communications and photonic quantum information processing.