Excerpt: [T]he following three trustee duties especially apply to ERISA fiduciaries: Duty of Loyalty ? The fiduciary must not engage in acts of self-dealing. This is perhaps the most fundamental duty. Duty to Keep Property Separate and Maintain Adequate Records ? Client property must be segregated from the property of the fiduciary and adequate records must be kept. Duty of Prudent Investment ? The fiduciary who manages investments has a duty to comply with the prudent investor rule unless otherwise agreed to with the client.