Organic bonded abrasive tools, having controlled microstructures, comprise a relatively low volume percentage of abrasive grain and a relatively low hardness grade, but are characterized by the excellent mechanical strength and efficient grinding performance of much harder grade, lower porosity tools, especially in versatile grinding processes, such as centerless grinding. A method for centerless grinding with these tools is provided. Methods for making the abrasive tools utilizing agglomerated abrasive grain are described.