We analyze the role of training in mitigating the negative impact of technical and organizational changes on the employment of older workers. Using a panel of French firms in the late 1990s, our empirical analysis confirms that new technologies and some innovative workplace practices are biased against older workers. The use of the Internet and the adoption of computer networks tend to increase the wage share of middle-aged workers and to reduce the share of workers older than 50. By contrast, the reduction of the number of hierarchical layers is favourable to older workers. Training contributes to protect older workers in terms of employment and/or of wages.Nous analysons dans quelle mesure la formation peut atténuer les effets défavorable...