Animals have an anxiety-reducing effect on humans. However, in the search for which interventions are the most effective, one notices that studies in this field are not comparable as they all use different designs. Hereby, we investigated the anxiety reducing abilities of different animals and a plant using a public speaking task with identical set-ups and measures in all conditions. After speech anxiety was induced in university students (n = 71), they were presented with either a dog, a fish, a plant, or were left alone (control condition) for an intervention phase of 5 minutes. Anxiety measures were taken at five different points throughout the testing procedure. When comparing the participants' levels of anxiety before and after the intervention, we found that all students showed reduced anxiety levels in the experimental conditions, with no differences among the types of intervention, while no such effect was found for participants in the control condition. Our results not only demonstrate a new perspective in research on animal-assisted activities by presenting a more systematic and analytic approach to research in this field, but more importantly, they confirm the necessity for research guidelines for animal-assisted activities across the different disciplines involved, and question the unique importance and necessity of the involvement of animals in interventional practice.Animals and plants are part of people's daily lives, and it is impossible even in major cities to walk around without seeing plants on balconies or people taking their dogs for a walk. Although several theories exist to explain the importance of human-animal relations (Wilson 1984;Grinde 2002) and the possible advantages of a good relationship between people and companion animals, for example, for the social, emotional, and cognitive development in children (see Endenburg and van Lith 2011 for a review), very little is known empirically about the influence of animals and plants on human emotions. Nevertheless, animal-assisted activities are being introduced into a wide range 267 Anthrozoös