Type Ia Supernovae are important contributors of iron and energy to the interstellar medium, as well as crucial cosmological probes. Understanding the nature of SNIa progenitors is fundamental for many astrophysical issues, due to the impact on the rate of their explosions as their parent stellar systems evolve, and because of the possible different characteristics of low and high redshift events. In this talk, starting from the major observational evidences, I will illustrate various evolutionary channels potentially leading to Type Ia SN events, and discuss their ability to meet the observational constraints. The second part of the talk will be devoted to the distribution of the delay times of SNIa progenitors, which has important implications for the evolution of galaxies. Theoretical models and empirical determinations will be illustrated and discussed. Finally, I will focus on the relation between the rate of SNIa events and the properties of the parent stellar population as a mean to derive clues on the progenitors.