The NEMO-3 experiment measured the half-life of the
2
ν
β
β
decay and searched for the
0
ν
β
β
decay of
116
Cd
. Using 410 g of
116
Cd
installed in the detector with an exposure of 5.26 y, (
4968
±
74
) events corresponding to the
2
ν
β
β
decay of
116
Cd
to the ground state of
116
Sn
have been observed with a signal to background ratio of about 12. The half-life of the
2
ν
β
β
decay has been measured to be
T
2
ν
1
/
2
=
[
2.74
±
0.04
(
stat
)
±
0.18
(
syst
)
]
×
1
0
19
y
. No events have been observed above the expected background while searching for
0
ν
β
β
decay. The corresponding limit on the half-life is determined to be
T
0
ν
1
/
2
≥
1.0
×
1
0
23
y
at the 90% C.L. which corresponds to an upper limit on the effective Majorana neutrino mass of
⟨
m
ν
⟩
≤
1.4
–
2.5
eV
depending on the nuclear matrix elements considered. Limits on other mechanisms generating
0
ν
β
β
decay such as the exchange of R-parity violating supersymmetric particles, right-handed currents and majoron emission are also obtained
