Being agglutinative or flexive are not properties of entire languages, nor are they simple properties. There is a whole ränge of simple properties, all logically independent ofeach other, prominently including those ofseparation/ cumulation and invariance/variance. They are all properties ofindividual wordforms, and again there is no logical necessityfor these to agree in their property sets. This creates a huge potential for heterogeneity within andfor diversity across languages, which, if realized to the fall, would render morphological typology unviable. However, an examination ofsplits between Separation and cumulation and between invariance and variance along the lines ofword-classes, ofsubsets within single word-classes, of morphological categories, and ofterms ofcategories suggests that mixtures between agglutination and flexion, though multifarious, are not random. Ifgrammars arefound to be less heterogeneous, and languages less diverse, than they could be, this can be due to universal, timeless principles or to regularities ofchange. Both play a wie in shaping morphological Systems.