Place the water and pearl barley in a large saucepan over high heat and bring to the boil. Reduce heat to low and simmer for 30-35 minutes or until tender. Rinse under cold running water. Drain.
Meanwhile, combine the paprika and cayenne pepper in a large bowl. Add the chicken and toss to lightly coat. Preheat a chargrill on medium-high. Add the chicken and cook for 5 minutes each side or until just cooked through.
Cook the beans in a saucepan of lightly salted boiling water for 2 minutes or until bright green and tender crisp. Rinse under cold running water. Drain.
Whisk together the lime juice and oil in a small bowl. Combine the pearl barley, beans, lime juice mixture, capsicum, shallot and 1/2 cup of coriander in a large bowl. Season with pepper.
Thinly slice the chicken across the grain. Divide the salad among serving plates. Sprinkle with the remaining coriander and top with the chicken. Serve with yoghurt and lime wedges.