An analysis of the forest transport industry is made. The results are based on a survey of a select sample of 79 forest transport service firms, and interviews with clients and suppliers. The analysis allowed a detailed explanation of the whole competitive environment in which forest transport firms operate, determining a low attractive of the industry, hence their profitability. Cost leadership is the strategy that dominates the industry. Therefore, size is a relevant factor to improve the competitive position of the firm before its suppliers and clients. Size represents a series of decisions and strategic commitments through time with the forest transport industry. The analysis of some particular firms, based on the resourced based view of the firm and activities system and their segmentation into strategic groups, allowed to define and recognize the key activities and singularities that allow these firms to operate with advantages in efficiency and profitability, within low average performance business. Some large and medium size firms investment and development criteria have positioned them considerably better than another firms in the industry.