19D06 $Q$- and plus-constructions
19D10 Algebraic $K$-theory of spaces
19D23 Symmetric monoidal categories [See also 18D10]
19D25 Karoubi-Villamayor-Gersten $K$-theory
19D35 Negative $K$-theory, NK and Nil
19D45 Higher symbols, Milnor $K$-theory
19D50 Computations of higher $K$-theory of rings [See also 13D15, 16E20]
19D55 $K$-theory and homology; cyclic homology and cohomology [See also 18G60]
19D99 None of the above, but in this section