Talking about informality makes reference to a concept that encompasses many
different activities outside the law. In this text informality is related to the one which is
present in labour market. This paper presents a theoretical and empirical review of
research about the determinants of informality in labour market. In particular, the search
that will guide this inquiry on the facts that determine the informality in labour market
is the one that have been done for Colombian case. Through a descriptive analysis with
data from the Encuesta 123 of informality in 2001 and modelling the probability of
belonging to informal sector in Colombia during the period 2002-2014, based on data
from the Encuesta Continua de Hogares (ECH) an the Gran Encuesta Integrada de
Hogares (GEIH) it is concluded that the determinants of informality are multiple and
have a marginal influence if they are considered separately. The results of this search
show that the causes of informality in Colombia are related mostly to two factors:
structural factors for the period between 2002 and 2014 and institutional factors
between 2008 and 2014.