diff --git a/lib/aiken-virtual-dex/types.ak b/lib/aiken-virtual-dex/types.ak
index 4fc60ec..2d3ec44 100644
--- a/lib/aiken-virtual-dex/types.ak
+++ b/lib/aiken-virtual-dex/types.ak
@@ -71,7 +71,6 @@ pub type TradeAddressRedeemer {
 // 6. ChangeAccount
 pub type ChangeAddressDatum {
   ChangeNormalDatum
-  ChangeEmergencyDatum { valid_since: Int }
 }
 
 pub type ChangeAddressRedeemer {
@@ -82,6 +81,7 @@ pub type ChangeAddressRedeemer {
 
 // 7. VirtualDex
 pub type VirtualDexDatum {
+  account_number: Int,
   long_token: (PolicyId, AssetName),
   short_token: (PolicyId, AssetName),
   price: Int,
@@ -90,9 +90,10 @@ pub type VirtualDexDatum {
 }
 
 pub type VirtualDexRedeemer {
-  TakeOrder
-  CancelOrder
+  TakeOrder { order_taker: Address }
   MassTakeOrder { take_order_output: OutputReference }
+  CancelOrder
+  EmergencyCancel
 }
 
 // 8. EmergencyToken
diff --git a/lib/aiken-virtual-dex/validators/virtual_dex.ak b/lib/aiken-virtual-dex/validators/virtual_dex.ak
index dca4e54..90b4c5c 100644
--- a/lib/aiken-virtual-dex/validators/virtual_dex.ak
+++ b/lib/aiken-virtual-dex/validators/virtual_dex.ak
@@ -2,8 +2,8 @@ use aiken/transaction.{InlineDatum, ScriptContext, Spend, Transaction}
 use aiken/transaction/value.{PolicyId}
 use aiken_virtual_dex/common.{inputs_with}
 use aiken_virtual_dex/types.{
-  CancelOrder, MassTakeOrder, OracleDatum, TakeOrder, VirtualDexDatum,
-  VirtualDexRedeemer,
+  CancelOrder, EmergencyCancel, MassTakeOrder, OracleDatum, TakeOrder,
+  VirtualDexDatum, VirtualDexRedeemer,
 }
 
 // pub fn valid_virtual_dex_redeemer(redeemers: Dict<ScriptPurpose, Data>) -> Bool {
@@ -34,9 +34,10 @@ pub fn virtual_dex_logic(
     //   CreateContent { content_hash: _, owner: _ } -> True
     //   _ -> False
     // }
-    TakeOrder -> True
+    TakeOrder { .. } -> True
 
     // for each script inputs, calculate the total should pay amount
     CancelOrder -> True
+    EmergencyCancel -> True
   }
 }
diff --git a/specs/0_scripts.md b/specs/0_scripts.md
index 65e8631..4e0ec8b 100644
--- a/specs/0_scripts.md
+++ b/specs/0_scripts.md
@@ -26,7 +26,7 @@ There are in total 7 scripts for the DeltaDeFi virtual dex to work. Below provid
 
    - The script to be compiled into different addresses according to account number, storing the change UTxO after transaction.
 
-7. VirtualDEX
+7. VirtualDEX - [specification](./7_virtual_dex)
 
    - The script governing the transaction logic.
 
diff --git a/specs/5_trade_account.md b/specs/5_trade_account.md
index a37933e..7db383b 100644
--- a/specs/5_trade_account.md
+++ b/specs/5_trade_account.md
@@ -23,7 +23,7 @@
    - Reference to account info utxo
    - Signed by operation key & owner
 
-2. Emergency operation - Redeemer `TradeEmergencyAction {new_owner_pub_key, new_owner_stake_cred}`
+2. Emergency operation - Redeemer `TradeEmergencyAction {withdraw_output}`
 
    - Reference to account info utxo
    - Signed by owner
diff --git a/specs/7_virtual_dex.md b/specs/7_virtual_dex.md
new file mode 100644
index 0000000..b1c0f0e
--- /dev/null
+++ b/specs/7_virtual_dex.md
@@ -0,0 +1,37 @@
+# Specification - VirtualDex
+
+## Parameter
+
+- `utxo_ref`: UTxO to be spent at minting
+
+## Datum
+
+- `account_number`: The account number of owner of order
+- `long_token`: The `AssetClass` of token in long side
+- `short_token`: The `AssetClass` of token in short side
+- `price`: Order exchange in a rate of `price` \* `long token` = `short token`
+- `is_lot_long`: If the user is selling short token for long token
+- `log_size`: Quantity of `long token` in this order
+
+## User Action
+
+1. Core logic of taking orders - Redeemer `TakeOrder {order_taker}`
+
+   - Reference to oracle utxo
+   - Reference to account info utxo of ann account owners
+   - Accumulate proceeds supposed send to order creators, check output value to them
+   - Cumulated amount send to `order_taker`
+   - Signed by operation owner
+
+2. Bypassing check if any other redeemer is with the core logic - Redeemer `MassTakeOrder { take_order_output }`
+
+   - The output provided by redeemer is with correct redeemer of `TakeOrder`
+
+3. Cancelling order which is mistakenly listed onchain - Redeemer `CancelOrder`
+
+   - signed by both `operating_key` and owner
+
+4. Emergency operation - Redeemer `EmergencyCancel`
+
+   - Reference to account info utxo
+   - `EmergencyToken` is burnt in current transaction