Despite the impressive developments that materials science has achieved in the last decades, there are still much more challenges to be solved, and chemical, physical, and biological phenomena to be understood in the field. This has the main goal of creating environmentally-friendly, more efficient and cheaper materials, and processes for their production; materials science will always offer endless opportunities for research and development. Nowadays, it is thought that ionic interactions are key factors for understanding many fundamental phenomena in materials science. Thus, this work discusses practical applications of emerging and classic ionic systems -ionic liquids and ionic polymerizations- in the development of new materials and efficient processes for their fabrication. The discussed topics are illustrated with potential and/or established applications. The novel and efficient methods proposed herein permit the preparation of new functional polymers, smart materials, and systems based on ionic interactions. These new methods and materials might certainly have a positive impact on the society and its constant search for new and better materials.