diff --git a/napi-pallas/src/validations/alonzo.rs b/napi-pallas/src/validations/alonzo.rs
index dace7cf..1496249 100644
--- a/napi-pallas/src/validations/alonzo.rs
+++ b/napi-pallas/src/validations/alonzo.rs
@@ -1,8 +1,271 @@
-use pallas::ledger::primitives::alonzo::MintedTx;
+use pallas::{
+  applying::{
+    alonzo::{
+      check_auxiliary_data, check_fee, check_ins_and_collateral_in_utxos, check_ins_not_empty,
+      check_languages, check_min_lovelace, check_minting, check_network_id, check_output_val_size,
+      check_preservation_of_value, check_script_data_hash, check_tx_ex_units, check_tx_size,
+      check_tx_validity_interval, check_witness_set,
+    },
+    utils::{get_alonzo_comp_tx_size, AlonzoProtParams, FeePolicy},
+    Environment, MultiEraProtParams, UTxOs,
+  },
+  ledger::primitives::alonzo::{MintedTx, TransactionBody},
+};
 
-use crate::Validations;
+use crate::{Validation, Validations};
+
+use super::validate::set_description;
+
+// & The following validation requires the size and the protocol params
+fn validate_alonzo_tx_size(size: &Option<u64>, prot_pps: &AlonzoProtParams) -> Validation {
+  match size {
+    Some(size_value) => {
+      let res = check_tx_size(&size_value, &prot_pps);
+      let description = set_description(
+        &res,
+        "The transaction size does not exceed the protocol limit.".to_string(),
+      );
+      return Validation::new()
+        .with_name("Transaction size".to_string())
+        .with_value(res.is_ok())
+        .with_description(description);
+    }
+    None => {
+      return Validation::new()
+        .with_name("Transaction size".to_string())
+        .with_value(false)
+        .with_description("The transaction size could not be obtained.".to_string());
+    }
+  }
+}
+
+// & The following validations require the transaction
+fn validate_alonzo_ins_not_empty(mtx_a: &MintedTx) -> Validation {
+  let res = check_ins_not_empty(&mtx_a.transaction_body);
+  let description = set_description(
+    &res,
+    "The set of transaction inputs is not empty.".to_string(),
+  );
+  return Validation::new()
+    .with_name("Non empty inputs".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+fn validate_alonzo_auxiliary_data(mtx_a: &MintedTx) -> Validation {
+  let tx_body: &TransactionBody = &mtx_a.transaction_body;
+  let res = check_auxiliary_data(&tx_body, mtx_a);
+  let description = set_description(
+    &res,
+    "The auxiliary data of the transaction is valid.".to_string(),
+  );
+  return Validation::new()
+    .with_name("Auxiliary data".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+fn validate_alonzo_script_data_hash(mtx_a: &MintedTx) -> Validation {
+  let tx_body: &TransactionBody = &mtx_a.transaction_body;
+  let res = check_script_data_hash(&tx_body, mtx_a);
+  let description = set_description(
+    &res,
+    "The script data integrity hash matches the hash of the redeemers, languages and datums of the transaction witness set.".to_string(),
+  );
+  return Validation::new()
+    .with_name("Script data hash".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+fn validate_alonzo_minting(mtx_a: &MintedTx) -> Validation {
+  let tx_body: &TransactionBody = &mtx_a.transaction_body;
+  let res = check_minting(&tx_body, mtx_a);
+  let description = set_description(
+    &res,
+    "Each minted / burned asset is paired with an appropriate native script or Plutus script."
+      .to_string(),
+  );
+  return Validation::new()
+    .with_name("Minting".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+// & The following validations require the transaction and the protocol params
+fn validate_alonzo_min_lovelace(mtx_a: &MintedTx, prot_pps: &AlonzoProtParams) -> Validation {
+  let tx_body: &TransactionBody = &mtx_a.transaction_body;
+  let res = check_min_lovelace(&tx_body, &prot_pps);
+  let description = set_description(
+    &res,
+    "All transaction outputs (regular outputs and collateral outputs) should contain at least the minimum lovelace".to_string(),
+  );
+  return Validation::new()
+    .with_name("Minimum lovelace".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+fn validate_alonzo_output_val_size(mtx_a: &MintedTx, prot_pps: &AlonzoProtParams) -> Validation {
+  let tx_body: &TransactionBody = &mtx_a.transaction_body;
+  let res = check_output_val_size(&tx_body, &prot_pps);
+  let description = set_description(
+    &res,
+    "The size of the value in each of the transaction outputs (regular outputs and collateral outputs) is not greater than the maximum allowed".to_string(),
+  );
+  return Validation::new()
+    .with_name("Minimum lovelace".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+fn validate_alonzo_tx_ex_units(mtx_a: &MintedTx, prot_pps: &AlonzoProtParams) -> Validation {
+  let res = check_tx_ex_units(mtx_a, &prot_pps);
+  let description = set_description(
+    &res,
+    "The size of the value in each of the transaction outputs (regular outputs and collateral outputs) is not greater than the maximum allowed".to_string(),
+  );
+  return Validation::new()
+    .with_name("Minimum lovelace".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+fn validate_alonzo_languages(mtx_a: &MintedTx, prot_pps: &AlonzoProtParams) -> Validation {
+  let res = check_languages(mtx_a, &prot_pps);
+  let description = set_description(
+    &res,
+    "The required script languages are included in the protocol parameters.".to_string(),
+  );
+  return Validation::new()
+    .with_name("Minimum lovelace".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+// & The following validation requires the transaction and the network id
+fn validate_alonzo_network_id(mtx_a: &MintedTx, network_id: &u8) -> Validation {
+  let res = check_network_id(&mtx_a.transaction_body, network_id);
+  let description = set_description(
+    &res,
+    "The network ID of each output matches the global network ID.".to_string(),
+  );
+  return Validation::new()
+    .with_name("Network ID".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+// & The following validations require the transaction and the block slot
+fn validate_alonzo_tx_validity_interval(mtx_a: &MintedTx, block_slot: &u64) -> Validation {
+  let res = check_tx_validity_interval(&mtx_a.transaction_body, mtx_a, block_slot);
+  let description = set_description(
+    &res,
+    "The upper bound of the validity time interval is suitable for script execution: if there are minting policies, native scripts or Plutus scripts involved in the transaction, and if the upper bound of its validity interval is a finite number, then it can be translated to system time.".to_string(),
+  );
+  return Validation::new()
+    .with_name("Transaction validity interval".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+// & The following validations require the transaction and its utxos
+fn validate_alonzo_ins_and_collateral_in_utxos(mtx_a: &MintedTx, utxos: &UTxOs) -> Validation {
+  let res = check_ins_and_collateral_in_utxos(&mtx_a.transaction_body, utxos);
+  let description = set_description(
+    &res,
+    "All transaction inputs and collateral inputs are in the set of (yet) unspent transaction outputs.".to_string(),
+  );
+  return Validation::new()
+    .with_name("Inputs and collateral in UTxOs".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+fn validate_alonzo_preservation_of_value(mtx_a: &MintedTx, utxos: &UTxOs) -> Validation {
+  let res = check_preservation_of_value(&mtx_a.transaction_body, utxos);
+  let description = set_description(
+    &res,
+    "The preservation of value property holds.".to_string(),
+  );
+  return Validation::new()
+    .with_name("Preservation of value".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+fn validate_alonzo_witness_set(mtx_a: &MintedTx, utxos: &UTxOs) -> Validation {
+  let res = check_witness_set(mtx_a, utxos);
+  let description = set_description(&res, "The transaction witness set is valid.".to_string());
+  return Validation::new()
+    .with_name("Witness set".to_string())
+    .with_value(res.is_ok())
+    .with_description(description);
+}
+
+// & The following validation requires the transaction, its utxos and the protocol params
+fn validate_alonzo_fee(mtx_a: &MintedTx, utxos: &UTxOs, prot_pps: &AlonzoProtParams) -> Validation {
+  let tx_body: &TransactionBody = &mtx_a.transaction_body;
+  let size: &Option<u64> = &get_alonzo_comp_tx_size(tx_body);
+  match size {
+    Some(size_value) => {
+      let res = check_fee(tx_body, size_value, mtx_a, utxos, prot_pps);
+      let description = set_description(
+        &res,
+        "The fee paid by the transaction should be greater than or equal to the minimum fee."
+          .to_string(),
+      );
+      return Validation::new()
+        .with_name("Fee".to_string())
+        .with_value(res.is_ok())
+        .with_description(description);
+    }
+    None => {
+      return Validation::new()
+        .with_name("Fee".to_string())
+        .with_value(false)
+        .with_description("The size could not be obtained.".to_string());
+    }
+  }
+}
 
 pub fn validate_alonzo(mtx_a: &MintedTx) -> Validations {
-  let out = Validations::new().with_era("Alonzo".to_string());
+  let tx_body: &TransactionBody = &mtx_a.transaction_body;
+  let size: &Option<u64> = &get_alonzo_comp_tx_size(tx_body);
+  let prot_params = AlonzoProtParams {
+    fee_policy: FeePolicy {
+      summand: 155381,
+      multiplier: 44,
+    },
+    max_tx_size: 16384,
+    max_block_ex_mem: 62000000,
+    max_block_ex_steps: 20000000000,
+    max_tx_ex_mem: 14000000,
+    max_tx_ex_steps: 10000000000,
+    max_val_size: 5000,
+    collateral_percent: 150,
+    max_collateral_inputs: 3,
+    coins_per_utxo_word: 4310,
+  };
+
+  let env: Environment = Environment {
+    prot_params: MultiEraProtParams::Alonzo(prot_params.clone()),
+    prot_magic: 764824073, // Mainnet. For preprod: 1. For preview: 2
+    block_slot: 72316896,  // TODO: Must be an input
+    network_id: 1,         // Mainnet. For preprod: 0. For preview: 0
+  };
+  let out = Validations::new()
+    .with_era("Alonzo".to_string())
+    .add_new_validation(validate_alonzo_tx_size(size, &prot_params))
+    .add_new_validation(validate_alonzo_ins_not_empty(mtx_a))
+    .add_new_validation(validate_alonzo_auxiliary_data(mtx_a))
+    .add_new_validation(validate_alonzo_script_data_hash(mtx_a))
+    .add_new_validation(validate_alonzo_minting(mtx_a))
+    .add_new_validation(validate_alonzo_min_lovelace(mtx_a, &prot_params))
+    .add_new_validation(validate_alonzo_output_val_size(mtx_a, &prot_params))
+    .add_new_validation(validate_alonzo_tx_ex_units(mtx_a, &prot_params))
+    .add_new_validation(validate_alonzo_languages(mtx_a, &prot_params))
+    .add_new_validation(validate_alonzo_network_id(mtx_a, &env.network_id))
+    .add_new_validation(validate_alonzo_tx_validity_interval(mtx_a, &env.block_slot));
   out
 }