You will not find them so common anymore.

The commonwealth is fifty-one countries that all share a  common origin of British monarchs.  The goals of the Commonwealth are to promote equal education opportunities, improve healthcare and economic strength.  Racial acceptance is another thing strove for by the Commonwealth.  South Africa's introduction of apartheid caused the government to withdraw from the Commonwealth.  South Africa was included again in 1994 with the removal of apartheid and creation of free elections.  in 199 5 Nigeria was suspended for executing political prisoners, readmitted in 1999.
Every four years the Commonwealth games are held.  These games are very much like a smaller scale Olympics including only athletes from Commonwealth countries.  The last games were held in Delhi India and were ridden with improperly built facilities.  The games have been held 4 times in Canada.  In Hamilton(1930), Vancouver(1954),  Edmonton(1978),and Victoria(1994).  The games have had 4 different names. These names are, British Empire Games(1930-50), British Empire and Commonwealth Games(1954-1966) British Commonwealth Games (1970-74) and finally just the Commonwealth games from (1978 -present)
While the group is called the Commonwealth a common wealth is not shared.  There are highly developed member countries, Canada, Australia and England but also third world countries, Sierra Leone, Mozambique and Bangladesh.  Money and help are given to these countries but usually only in times of extreme need.  An illusion of common wealth is promoted but it is only smoke and mirrors.

Yes the title of this post is a Princess Bride quote.