CASUALTY insurance is a very broad category of coverage (sometimes generally referred to as liability insurance) against loss of property, damage or other liabilities suffered by 3rd parties for which the insured (1st party) might be proved to be ultimately liable.  The most common type of Casualty insurance remains general public liability insurance.  Often, jurisdictions make certain types of casualty compulsory, as is often the case with 3rd party motor insurance and workers’ compensation insurance.  Be sure to work with your insurance broker to review jurisdictional insurance requirements to ensure your company has locally compliant solutions.  There are some very technical sub-sets of Casualty insurance such as professional indemnity (often called Errors & Omission) insurance, environmental insurance, and Cyber insurance which is a very fast growing area of insurance.