How many letters does the top answer for “demanding strict attention to rules and procedures” have?

The most common answer is rigorous (8 letters).

Crossword clue: demanding strict attention to rules and procedures

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

rigorous 8 letters wn-def

demanding strict attention to rules and procedures

stringent 9 letters wn-def

demanding strict attention to rules and procedures