**1. Introduction and Scope**

Microstructure design is key in targeting the desired material's properties. It is therefore essential to understand the relations between properties and microstructure and how they are driven via a specific process [1–5]. The following five journals contribute to this topic: *Aerospace, Alloys, Crystals, Materials, and Metals*. Contributions related to microstructure design and characterization are collected in this topic, together with their relation to the mechanics, fatigue, wear, and corrosion resistance of different kinds of metals and alloys. The goal of this Topic is to present contributions related to the relationship between the microstructure and properties of metals and alloys for different applications, including aeronautical and aerospace applications. Different process routes are considered (thermo-mechanical routes and additive manufacturing) in this topic. Welding is a mandatory issue in many applications: this is why contributions related to welding are also included in this topic.
