Several embodiments disclosed herein relate to the compositions comprising engineered Natural Killer (NK) cells that express a chimeric receptor, the chimeric receptor imparting to the NK cells an enhanced ability to target specific cells, such as cancerous cells or those affected by an infectious disease. Several embodiments relate to NK cells that target cells expressing natural ligands of NKG2D, where the NK cells comprise transmembrane and/or signaling domains that lead to cytotoxic and/or cytolytic effects when the NK cells bind a target cell. Uses of NK cell compositions to treat diseases are also provided for in several embodiments.