More humanity means fewer humans. If you believe with us that in the future neither Earth nor the UK will be able to sustain larger populations than they do today, please help to support our work. The Optimum Population Trust is a registered charity funded by membership, donations and bequests. It receives no political or government funding and is independent of political or commercial interests.

You can make a donation by cheque (made out to the Optimum Population Trust and sent to the Membership Secretary at the address below) or online with tax relief using JustGiving by clicking the button below:

You can join online (which is preferable) or you can print out a Membership Form here.

My personal details are provided for use by OPT, on the understanding that the data will not be divulged to other organisations — commercial or otherwise — without my permission.

Join online — Step 1: Enter your details

Title
First Name(s)
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How did you hear about us?
I am a UK taxpayer and I want OPT to treat all my donations from today as Gift Aid until further notice.

You will need to pay an amount of income tax / capital gains tax at least equal to the tax the charity will reclaim in the tax year that the gift was received.

Now please click on the Send button and send the email which is created.

Please then go to Step 2 to pay by credit/ debit card or your Paypal account.

Join online — Step 2: Payment

Please select your region: UK Overseas