Models of cooperative and noncooperative behaviour opened the household ‘black box’ and allowed for individual treatment of partners in couples. However, labour supply literature has so far largely ignored a broader issue – the distinction of single versus multi-family
(‘complex’) households. We propose a method to account for multi-family household structure by borrowing from recent applications of the collective model to identify the degree of sharing. We assume that each household is characterized by a between-family sharing parameter, which
is calibrated on estimated preferences, observed labour market status and other characteristics. We apply the method to Polish labour market data.