## Saturna Sustainable  Equity Fund

**Ticker Symbol: SEEFX**

**March 29, 2016**

### SUMMARY PROSPECTUS

Before you invest, you may want to review Saturna Sustainable Equity Fund's prospectus, which contains moreinformation about the Fund and its risks. You can find the Fund's **prospectus** and other information about theFund, including the **statement of additional information** and most recent reports to shareowners, online atwww.saturnasustainable.com/prospectus. You can also get this information at no cost by calling 1-800-728-8762or by sending an email request to info@saturna.com. The Fund's prospectus and statement of additionalinformation, both dated March 29, 2016, are incorporated by reference into this Summary Prospectus.

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| Saturna Sustainable Equity Fund | SEEFX |
|---------------------------------|-------|

### Investment Objective

Capital appreciation. 

### Fees and Expenses

**Shareowner Fees**

There are no fees that shareowners pay directly from their investments, such as charges for purchases, redemptions, and exchanges of shares.

| **Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment) |
|----------------------------------------------------------------------------------------------------------------------|
| Management Fees                                                                                                      | 0.65% |
| Distribution (12b-1) Fees                                                                                            | 0.25% |
| Other Expenses¹                                                                                                 | 0.33% |
| Total Annual Fund Operating Expenses                                                                                 | 1.23% |
| Fee Waiver and Expense Reimbursement                                                                                 | 0.24% |
| Total Annual Fund Operating Expenses after Fee Waiver and Expense Reimbursement²                                | 0.99% |

¹ The "Other Expenses" are based on estimated amounts for the initial fiscal year.

² The investment adviser has committed through March 31, 2017, to waive fees and/or reimburse expenses to the extent necessary to ensure that the Fund's net operating expenses, excluding brokerage commissions, interest, taxes, and extraordinary expenses do not exceed the net operating expense ratio of 0.99%. This expense limitation agreement may be changed or terminated only with approval of the Board of Trustees.

**Example**

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.

The Example assumes you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. Although actual costs may be higher or lower, based on these assumptions, your costs would be:

| 1 year | 3 years | 5 years | 10 years |
|--------|---------|---------|----------|
| $125   | $390    | $676    | $1,489   |

**Portfolio Turnover**

The Fund may have transaction costs, such as commissions and a bid-ask spread, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the example, affect your after-tax returns. During the most recent fiscal year, the Fund's portfolio turnover rate was 52.73% of the average value of its portfolio.

### Principal Investment Strategies

Under normal conditions, the Fund invests at least 80% of its assets in equities of issuers located throughout the world that the Fund's adviser believes demonstrate sustainable characteristics. For purposes of this investment policy, the Fund's adviser considers issuers with sustainable characteristics to be those issuers that are generally larger, more established, consistently profitable, and financially strong, and with low risks in the areas of the environment, social responsibility, and corporate governance ("ESG"). The Fund's adviser uses an internally developed ESG rating system to identify issuers that the Fund's adviser believes present low ESG risks. 

The Fund diversifies its investments across industries, companies, and countries, and generally follows a large and mid-cap value investment style. The Fund prefers seasoned companies that are expected to grow revenue and earnings, favoring equities of companies trading for less than the adviser's assessment of their intrinsic value, which typically means companies with low price/earnings multiples, strong balance sheets, and higher dividend yields. The Fund may invest up to 30% of assets in companies with headquarters in developing countries.

### Principal Risks of Investing

**Market risk:** The value of the Fund's shares rises and falls as the market value of the securities in which the Fund invests goes up and down. The market value of securities will fluctuate, sometimes significantly and unpredictably, with stocks generally being more volatile than bonds. When you redeem your shares, they may be worth more or less than what you paid for them. Only consider investing in the Fund if you are willing to accept the risk that you may lose money.

**Investment strategy risk:**The adviser believes that sustainable investing may mitigate security-specific risk, but the screens used in connection with sustainable investing reduces the investable universe, which limits opportunities and may increase the risk of loss during market declines. In addition, the Fund has a relatively limited operating history, having commenced investment operations in March 2015, and its limited performance history does not provide extensive information on how the Funds may perform in different market conditions.

| Saturna Sustainable Equity Fund | SEEFX |
|---------------------------------|-------|

**Equity securities risk:** Equity securities may experience significant volatility in response to economic or market conditions or adverse events that affect a particular industry, sector, or company. Although the Fund may invest in companies of all sizes, the Fund tends to favor larger companies and, to a lesser extent, midsize companies. Larger companies may have slower rates of growth as compared to smaller, faster-growing companies. Midsize companies may have more limited financial resources, products, or services, and tend to be more sensitive to changing economic or market conditions. 

**Foreign investing risk:** Foreign investing involves risks not normally associated with US securities. These risks include fluctuations in currency exchange rates, less public information about securities, less governmental market supervision, and lack of uniform financial, social, and political standards. Foreign investing heightens the risk of confiscatory taxation, seizure or nationalization of assets, currency controls, or adverse political or social developments that affect investments.

The risks of investing in foreign securities typically are greater in less developed or emerging countries.

### Performance

This Prospectus does not show performance of the Fund because the Fund has not completed one full calendar year of operations as of the date of this prospectus. Future reports will show how the Fund's average annual total returns for the required time periods compare with the S&P Global 1200 Index.

Performance of the Fund, which provides some indication of the risks of investing in the Fund, will vary from year to year.

### Investment Adviser

Saturna Capital Corporation is the Saturna Sustainable Equity Fund's investment adviser.

### Portfolio Manager

Mr. Nicholas Kaiser MBA, CFA, chairman of Saturna Capital Corporation, is the person primarily responsible for the day-to-day management of the Saturna Sustainable Equity Fund. Mr. Peter Nielsen MBA, CFA, is the deputy portfolio manager. They have been the managers of the Fund since 2015.

### Purchase and Sale of Fund Shares

You may open an account and purchase shares by sending a completed application, a photocopy of a government-issued identity document, and a check for $10,000 or more ($100 for an IRA or retirement plan) payable to the Saturna Sustainable Equity Fund. Shareowners may purchase additional shares at any time in minimum amounts of $25.

Shareowners may redeem shares on any business day by several methods:

**Written request**

> 
Write: Sextant Mutual Funds          Box N          Bellingham, WA 98227-0596

Or Fax: 360-734-0755

**Telephone request**

> 
Call: 800-728-8762 or 360-734-9900

### Tax Information

Any distributions you receive from the Fund may be taxed as ordinary income, qualified dividend income, or capital gains.

### Financial Intermediary Compensation

If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund and its related companies may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary's website for more information.

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