A multi-signature address is an address that is associated with more than one private key. Multisig have lots of uses, wallet sharing, increased security and escrow. Further readings: Multisig, The Future of Bitcoin.

Part 1. Create Multisig Address

• To create a m-of-n multisig address, we need n public keys. You can easily get public key with respect to your address.
  
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  Right click any address to get public key
  
• Now we can create our multisig address
  
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  Click "New MultiSig" and fill in each public keys from step 1.
  
• You can find the newly created multisig address on "Addresses" and export this multisig address.
  
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  Export MultiSig address to your partner
  

Part 2. Send to multisig address
Send to multisig address is identical to your normal transaction, just provide your multisig address as recipient.

Part 3. Spend from multisig address
Here we'll describe how Alice and Bob spend FusionCoin from their 2-of-2 multisig address. This transaction needs to be signed with two private keys, one is hold by Alice, the other by Bob.

• Alice reviews her balance of her multisig addresses.
  
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  Check balance
  
• Alice starts creating transaction from the 2-of-2 multisig address.They each has a private key of that address in their wallet.
  
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  Create Transaction
  
• Alice sign the transaction with her private key, and export the raw transaction. Alice then needs to send this raw transaction to Bob(Email, BitMessage, SMS...).
  
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  Sign and export raw Transaction
  
• Bob import this raw transaction, he can see the transaction is already signed by a private key. Bob reviews the transactions and sign with his private key.
  
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  Import and Sign raw Transaction
  
• Now the transaction is signed by two private keys. Bob can simply click "Send" to broadcast the transaction.
  
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  Send transaction