Photoconductive switches were the key components that allowed the generation and detection of coherent broadband electromagnetic pulses at terahertz frequencies, opening the possibility for performing spectroscopy and,therefore, measuring complex dielectric properties of materials in this band, which was mostly unexplored. In this paper, we present a brief introduction to the operation principles of these devices. Subsequently, we present a review of the current state-of-the-art in this field and discuss the challenges to be faced in future development of these devices. Photoconductive switches were the key components that allowed the generation and detection of coherent broadband electromagnetic pulses at terahertz frequencies, opening the possibility for spectroscopy and, therefore, measuring complex dielectric properties of materials in this band, which was mostly unexplored. In this paper, we present a brief introduction to the operation principles of these devices. next present the review of the current state-of-the-art in this field and discuss the challenges to be faced in the future development of these devices.