A first part lists basic rules, taken from the string- and multiperipheral models, that a recursive quark fragmentation model should obey. A second part describes spin effects given by the classical "string + 3P0" mechanism of quark-antiquark pair creation, in pseudoscalar and vector meson production: Collins effect, jet handedness and "hidden spin" effects in unpolarized experiments. The last part constructs a recursive quantum-mechanical model of spin-dependent fragmentation. In a "ab initio" approach an integral equation must be solved as a preliminary task. With a "renormalized input", this task is reduced to an ordinary integration. A spin-dependent generalization of the symmetric Lund model is obtained.