matrix of first & last names into alphabetical order of last name without using the sort command?

How do I sort a matrix that contains first & last names, into alphabetical order of last name without using the sort command? I have a matrix of 2 columns but different lengths of names. But I need to put them in alphabetic order by last name without using the builtin sort function command. Maybe by using Find and char?

[Adam]

Just write your own sort function if you can't use the builtin. It's one of the standard algorithmic recipes with loads of different implementations that you can easily lookup.