Recognizing the ever-
increasing importance of
treaties as a
source of
international law and as a means of developing
peaceful
co-operation among
nations, whatever their
constitutional
and
social systems,
Noting that the
principles of
free consent and of
good
faith and the pacta sunt servanda
rule are universally recognized,
Believing that the codification and progressive
development of the
law of
treaties achieved in the present
Convention will
promote
the
purposes of the
United Nations set forth in the
Charter, namely, the
maintenance
of
international peace and
security, the
development of
friendly relations and
the
achievement of
co-operation among
nations,