Accounting/Payroll/HR Software for the PEO/ASO Industry. Web based payroll system. Microsoft Partner specializing in Dynamics GP and Microsoft CRM. ThinkWare is the leading provider of PEO and ASO software solutions. Since 1994, ThinkWare has been providing software solutions for PEO and ASO companies of all size. No other PEO software company can claim the success and growth rate of ThinkWare. ThinkWare relies upon advanced technology, industry knowledge and experience, and a proven development partner organization to develop solutions specifically designed to handle the unique challenges faced by PEO and ASO companies today.