diff --git a/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/Importer.java b/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/Importer.java
index bf18803ba0c..5828fc5dcfa 100644
--- a/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/Importer.java
+++ b/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/Importer.java
@@ -346,4 +346,27 @@ default Network importData(ReadOnlyDataSource dataSource, NetworkFactory network
     default void copy(ReadOnlyDataSource fromDataSource, DataSource toDataSource) {
         throw new UnsupportedOperationException("Copy not implemented");
     }
+
+    /**
+     * Update a given network with contents coming from a data source.
+     *
+     * @param network network
+     * @param dataSource data source
+     * @param parameters some properties to configure the import
+     * @param reportNode the reportNode used for functional logs
+     */
+    default void update(Network network, ReadOnlyDataSource dataSource, Properties parameters, ReportNode reportNode) {
+        update(network, dataSource, parameters);
+    }
+
+    /**
+     * Update a given network with contents coming from a data source.
+     *
+     * @param network network
+     * @param dataSource data source
+     * @param parameters some properties to configure the import
+     */
+    default void update(Network network, ReadOnlyDataSource dataSource, Properties parameters) {
+        throw new UnsupportedOperationException("Importer do not implement updates");
+    }
 }
diff --git a/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/Network.java b/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/Network.java
index 8197882ca70..764c862e2a3 100644
--- a/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/Network.java
+++ b/iidm/iidm-api/src/main/java/com/powsybl/iidm/network/Network.java
@@ -401,6 +401,29 @@ static void readAll(Path dir, Consumer<Network> consumer) throws IOException, In
         readAll(dir, false, LocalComputationManager.getDefault(), ImportConfig.CACHE.get(), consumer);
     }
 
+    default void update(ReadOnlyDataSource dataSource) {
+        update(dataSource, null);
+    }
+
+    default void update(ReadOnlyDataSource dataSource, Properties properties) {
+        update(dataSource, properties, ReportNode.NO_OP);
+    }
+
+    default void update(ReadOnlyDataSource dataSource, Properties parameters, ReportNode reportNode) {
+        update(dataSource, LocalComputationManager.getDefault(), ImportConfig.load(), parameters,
+                new ImportersServiceLoader(), reportNode);
+    }
+
+    default void update(ReadOnlyDataSource dataSource, ComputationManager computationManager, ImportConfig config, Properties parameters,
+                        ImportersLoader loader, ReportNode reportNode) {
+        Importer importer = Importer.find(dataSource, loader, computationManager, config);
+        if (importer != null) {
+            importer.update(this, dataSource, parameters, reportNode);
+        } else {
+            throw new PowsyblException(Importers.UNSUPPORTED_FILE_FORMAT_OR_INVALID_FILE);
+        }
+    }
+
     /**
      * A global bus/breaker view of the network.
      * <p>
diff --git a/iidm/iidm-api/src/test/java/com/powsybl/iidm/network/ImportersTest.java b/iidm/iidm-api/src/test/java/com/powsybl/iidm/network/ImportersTest.java
index 1c9ffe57b63..57812654c29 100644
--- a/iidm/iidm-api/src/test/java/com/powsybl/iidm/network/ImportersTest.java
+++ b/iidm/iidm-api/src/test/java/com/powsybl/iidm/network/ImportersTest.java
@@ -50,6 +50,7 @@ class ImportersTest extends AbstractConvertersTest {
     private final NetworkFactory networkFactory = new NetworkFactoryMock();
 
     @BeforeEach
+    @Override
     void setUp() throws IOException {
         super.setUp();
         Files.createFile(fileSystem.getPath(WORK_DIR + FOO_TST));
@@ -227,5 +228,18 @@ void loadNetworks() throws InterruptedException, ExecutionException, IOException
         assertEquals(2, isLoadPresent.size());
         isLoadPresent.forEach(Assertions::assertTrue);
     }
+
+    @Test
+    void updateNetwork() {
+        Network network = Network.read(path, computationManager, importConfigMock, null, networkFactory, loader, ReportNode.NO_OP);
+        assertNotNull(network);
+        Load load = network.getLoad("LOAD");
+        assertNotNull(load);
+
+        // The mocked network simulates P0 is not set in first import, but is read when we call update
+        assertTrue(Double.isNaN(load.getP0()));
+        network.update(DataSource.fromPath(path));
+        assertEquals(123.0, load.getP0());
+    }
 }
 
diff --git a/iidm/iidm-api/src/test/java/com/powsybl/iidm/network/NetworkFactoryMock.java b/iidm/iidm-api/src/test/java/com/powsybl/iidm/network/NetworkFactoryMock.java
index f4eafe5c307..6958187fb7d 100644
--- a/iidm/iidm-api/src/test/java/com/powsybl/iidm/network/NetworkFactoryMock.java
+++ b/iidm/iidm-api/src/test/java/com/powsybl/iidm/network/NetworkFactoryMock.java
@@ -9,6 +9,11 @@
 
 import java.time.ZoneOffset;
 import java.time.ZonedDateTime;
+import java.util.Properties;
+
+import com.powsybl.commons.datasource.ReadOnlyDataSource;
+import com.powsybl.commons.report.ReportNode;
+import com.powsybl.computation.ComputationManager;
 import org.mockito.Mockito;
 
 /**
@@ -34,6 +39,33 @@ public Network createNetwork(String id, String sourceFormat) {
         Mockito.when(load.getLoadType())
                 .thenAnswer(invocationOnMock -> loadType[0]);
 
+        // When called to be updated, rely on default method, that will call importer
+        Mockito.doCallRealMethod().when(network).update(
+                Mockito.any(ReadOnlyDataSource.class),
+                Mockito.any(ComputationManager.class),
+                Mockito.any(ImportConfig.class),
+                Mockito.nullable(Properties.class),
+                Mockito.any(ImportersLoader.class),
+                Mockito.any(ReportNode.class));
+        Mockito.doCallRealMethod().when(network).update(
+                Mockito.any(ReadOnlyDataSource.class),
+                Mockito.nullable(Properties.class),
+                Mockito.any(ReportNode.class));
+        Mockito.doCallRealMethod().when(network).update(
+                Mockito.any(ReadOnlyDataSource.class),
+                Mockito.nullable(Properties.class));
+        Mockito.doCallRealMethod().when(network).update(
+                Mockito.any(ReadOnlyDataSource.class));
+        // Allow setting a value for P0
+        double[] loadP = new double[1];
+        loadP[0] = Double.NaN;
+        Mockito.doAnswer(invocationOnMock -> {
+            loadP[0] = (double) invocationOnMock.getArguments()[0];
+            return load;
+        }).when(load).setP0(Mockito.anyDouble());
+        Mockito.when(load.getP0())
+                .thenAnswer(invocationOnMock -> loadP[0]);
+
         return network;
     }
 
diff --git a/iidm/iidm-api/src/test/java/com/powsybl/iidm/network/TestImporter.java b/iidm/iidm-api/src/test/java/com/powsybl/iidm/network/TestImporter.java
index 76f2c0b55a5..15ba6d72390 100644
--- a/iidm/iidm-api/src/test/java/com/powsybl/iidm/network/TestImporter.java
+++ b/iidm/iidm-api/src/test/java/com/powsybl/iidm/network/TestImporter.java
@@ -56,4 +56,19 @@ public Network importData(ReadOnlyDataSource dataSource, NetworkFactory networkF
         }
         return networkFactory.createNetwork("mock", "test");
     }
+
+    @Override
+    public void update(Network network, ReadOnlyDataSource dataSource, Properties parameters, ReportNode reportNode) {
+        if (reportNode != null) {
+            reportNode.newReportNode()
+                    .withMessageTemplate("test", "Update model ${model}")
+                    .withUntypedValue("model", "eurostagTutorialExample1")
+                    .add();
+        }
+        // Update a load in the network
+        Load load = network.getLoad("LOAD");
+        if (load != null) {
+            load.setP0(123.0);
+        }
+    }
 }