This lecture reports on work carried out in collaboration with Yan Zhao. We have developed a suite of density functionals. All four functionals are accurate for noncovalent interactions and medium-range correlation energy. The functional with broadest capability, M06, is uniquely well suited for good performance on both transition-metal and main group-chemistry; it also gives good results for barrier heights. Another functional, M06-L has no Hartree-Fock exchange, which allows for very fast calculations on large systems, and it is especially good for transition-metal chemistry and NMR chemical shieldings. M08-2X and an earlier version, M06-2X, have the very best performance for main-group thermochemistry, barrier heights, and noncovalent interactions. M06-HF has no one-electron self-interaction error and is the best functional for charge transfer spectroscopy. A general characteristic of the whole suite is the optimized inclusion of kinetic energy density and higher separate accuracy of medium-range exchange and correlation contributions with less cancellation of errors than previous functionals [1-4]; for example, the functionals are compatible with a range of Hartree-Fock exchange and, although one or another of them may be more highly recommended for one or another property or application, all four are better on average than the very popular B3LYP functional. A few sample applications, including catalytic systems [5,6] and nanomaterials [7], will also be discussed. Recent work on lattice constants, band gaps, and an improved version of M06-2X will be summarized if time permits. [1] "Design of Density Functionals by Combining the Method of Constraint Satisfaction with Parametrization for Thermochemistry, Thermochemical Kinetics, and Noncovalent Interactions," Zhao, Y. ; Schultz, N. E.; Truhlar, D. G.; J. Chem. Theory Comput. 2006, 2, 364-382. [2] "A New Local Density Functional for Main Group Thermochemistry, Transition Metal Bonding, Thermochemical Kinetics, and Noncovalent Interactions," Zhao, Y.; Truhlar, D. G. J. Chem. Phys. 2006, 125, 194101/1-18. [3] “The M06 Suite of Density Functionals for Main Group Thermochemistry, Thermochemical Kinetics, Noncovalent Interactions, Excited States, and Transition Elements: Two New Functionals and Systematic Testing of Four M06-Class Functionals and 12 Other Functionals,” Zhao, Y.; Truhlar, D. G. Theor. Chem. Acc. 2008, 120, 215-241. [4] "Density Functionals with Broad Applicability in Chemistry," Zhao, Y.; Truhlar, D. G. Acc. Chem. Res. 2008 41, 157-167. [5] “Attractive Noncovalent Interactions in Grubbs Second-Generation Ru Catalysts for Olefin Metathesis," Zhao, Y.; Truhlar, D. G. Org. Lett. 2007, 9, 1967-1970. [6] "Benchmark Data for Interactions in Zeolite Model Complexes and Their Use for Assessment and Validation of Electronic Structure Methods," Zhao, Y.; Truhlar, D. G. J. Phys. Chem. C 2008, 112, 6860-6868. [7] "Size-Selective Supramolecular Chemistry in a Hydrocarbon Nanoring," Zhao, Y.; Truhlar, D. G. J. Am. Chem. Soc.2007, 129, 8440-8442.