Nanocomposites have been widely studied for their dramatically improved properties, such as mechanical strength, thermoelectric performance, chemical reactivity, and optical properties. With new materials and nanomanufacturing techniques, new opportunities are further introduced to this long-running research direction. This issues have multiple interesting papers dedicated to this important topic. For mechanical properties, Hu et al. (DOI: 10.30919/esmm5f158) demonstrated the use of hydroxide (Ca(OH2) nano-spherulites (CNS) with <5 nm diameters as cross-linkers to achieve highly stretchable selfhealing nanocomposite hydrogel. For solid lubricant applications, Joseph et al. (DOI: 10.30919/esmm5f152) added MoS nanosheets to 2 plated Ni coatings to dramatically improve the microhardness and wear resistance of the obtained Ni-MoS2 composite.