Production of goods and services within the household, rather than through formal or informal market organizations. In pre-industrial societies, and in some less developed countries, a substantial proportion of economic activity takes this form. In modern economies it is less important, though this is partly a matter of accounting conventions. A considerable part of people's time even in advanced economies is taken up with tasks like cookery, cleaning, childcare, gardening, driving and car maintenance, and do-it-yourself building and decorating. All these can in principle be provided commercially, and are performed by employees in some households. These services are generally ignored in national income accounting.