Are there standard ways and guidelines on extending Unicode with custom user-defined character sets?

Question

In a linguistic project of mine I need to use symbols not contained in Unicode. I can draw the font, but would like to avoid overwriting characters defined by the standard. Are there any standard solutions for such cases? As reserved ranges etc. I'd need common Unicode-aware software to handle it seamlessly.

Answer 1

Start at the Wikipedia article on private use characters - there are indeed specific areas allocated for such purposes (Planes 15 and 16); maybe check ConScript Unicode Registry.