In this review paper, the methodology employed was undertaken according to the following steps. First, the literature was collected from the SCOPUS database due to it indexes the largest number of journals and is commonly used in engineering fields [12,13]. The initial search was performed on the 21st of January 2021 with the keywords "structural health monitoring" and with the aim of obtaining exclusively the non-contact literature, the specific query was: TITLE-ABS-KEY ("structural health monitoring" AND non-contact* OR noncontact* OR contactless). The boolean operators (AND, OR, *) are used to include entirely the non-contact literature and to incorporate potential literature with different spellings of non-contact. An initial 623 results were obtained, a further limit was imposed on only English language documents. The search was not limited to a time frame, resulting in 608 documents from 1994 to 2021 plotted in Figure 1. Then, the 608 articles were browsed and 92 irrelevant documents (e.g., medical fields) were excluded and subsequently were classified according to the main method/tool, Table 1 summarizes it. Figure 1: Research publications on the use of non-contact methods and tools in structural health monitoring.Table 1: Non-contact methods/tools in SHM. Methods Number of Articles Percentage Vision-based 146 28.29% Guided Waves 91 17.64% Ultrasound 49 9.50% Vibration 47 9.11% Magnetic Methods 33 6.40% Acoustic based 31 6.01% Displacement based 28 5.43% Thermal Inspection 18 3.49%