There are numerous ways in which you can now enhance the stability of ladders. Adding a bracket to the top or bottom of a ladder will increase the overall stability greatly.
The Working at Height Law requests that stability devices are used where practical to do so.

SCHEDULE 6
REQUIREMENTS FOR LADDERS
5.A portable ladder shall be prevented from slipping during use by -
(a) securing the stiles at or near their upper or lower ends;
(b) an effective anti-slip or other effective stability device; or
(c) any other arrangement of equivalent effectiveness.