During the last decade, airborne laser scanning has developed into an operational technique for bathymetric mapping. One of the operational systems for depth sounding is the Hawk Eye II system. In this report, we examine the possibilities for classification of bottom vegetation and substrates by experimental evaluation of the separability in laser data between different bottom types. We study a number of data variables from the Hawk Eye II system, which have the potential to describe the reflectivity and the roughness of the sea bottom. These variables are extracted from the pulse response, also denoted the waveform, of the emitted and reflected laser pulse from the water volume and the sea bottom. We also describe methods for correction of the waveform variables for depth, water turbidity, and laser system parameters. The corrected variables are studied over field patches which were documented by underwater video. The variables are evaluated separately, in combination with each other, and combined with laser depth data for test classification of the four bottom types Sand, Low Vegetation (Zostera marina), High Vegetation (Potamogeton perfoliatus) and Boulders. With the best combination of waveform variables and variables calculated from depth data, a total classification accuracy of about 70 % was obtained between these bottom types. Our results show that the waveform variables have a potential for significant improvement of the classification accuracy compared to when only depth data is used for classification of bottom substrates and vegetation. This report describes the initial work in the EMMA programme (Environmental Mapping and Monitoring with Airborne laser and digital images). The preliminary methods and results presented in this report will be further evaluated and developed using laser data and field data from several sites.