Inhibitors of mammalian target of rapamycin (mTOR) have been approved for the treatment of renal cell carcinoma and appear to have a role in the treatment of other malignancies. The primary objective of this drug review is to provide pharmacokinetic and dynamic properties of the commonly used drugs everolimus and temsirolimus. Additionally, information on clinical use, mechanism of action, bioanalysis, drug-drug interactions, alterations with disease or age, pharmacogenetics, and drug resistance is given. This overview should assist the treating medical oncologist in adjusting treatment with mTOR inhibitors to individual patient circumstances.