Index: src/include/lib/Paheko/Accounting/AdvancedSearch.php
==================================================================
--- src/include/lib/Paheko/Accounting/AdvancedSearch.php
+++ src/include/lib/Paheko/Accounting/AdvancedSearch.php
@@ -29,10 +29,16 @@
 		}
 
 		$types .= 'END';
 
 		return [
+			'line_id' => [
+				'label'    => null,
+				'type'     => 'integer',
+				'null'     => true,
+				'select'   => 'l.id',
+			],
 			'id' => [
 				'label'    => 'Numéro écriture',
 				'type'     => 'integer',
 				'null'     => false,
 				'select'   => 't.id',
@@ -273,11 +279,11 @@
 		$tables = 'acc_transactions AS t
 			INNER JOIN acc_transactions_lines AS l ON l.id_transaction = t.id
 			INNER JOIN acc_accounts AS a ON l.id_account = a.id
 			INNER JOIN acc_years AS y ON t.id_year = y.id
 			LEFT JOIN acc_projects AS p ON l.id_project = p.id';
-		return $this->makeList($query, $tables, 'id', true, ['id', 'account_code', 'debit', 'credit']);
+		return $this->makeList($query, $tables, 'id', true, ['id', 'account_code', 'line_id', 'debit', 'credit']);
 	}
 
 	public function defaults(): \stdClass
 	{
 		$group = [

Index: src/include/lib/Paheko/AdvancedSearch.php
==================================================================
--- src/include/lib/Paheko/AdvancedSearch.php
+++ src/include/lib/Paheko/AdvancedSearch.php

Index: src/templates/acc/accounts/journal.tpl
==================================================================
--- src/templates/acc/accounts/journal.tpl
+++ src/templates/acc/accounts/journal.tpl
@@ -81,11 +81,11 @@
 
 	{foreach from=$list->iterate() item="line"}
 		<tr>
 			{if $can_edit}
 			<td class="check">
-				{input type="checkbox" name="check[%s]"|args:$line.id_line value=$line.id default=0}
+				{input type="checkbox" name="selected[%s]"|args:$line.id_line value=$line.id default=0}
 			</td>
 			{/if}
 			<td class="num"><a href="{$admin_url}acc/transactions/details.php?id={$line.id}">#{$line.id}</a></td>
 			<td>{$line.date|date_short}</td>
 			{if $simple}

Index: src/templates/acc/search.tpl
==================================================================
--- src/templates/acc/search.tpl
+++ src/templates/acc/search.tpl
@@ -27,12 +27,13 @@
 	$credit = null;
 	?>
 
 	{foreach from=$list->iterate() item="row"}
 		<tr>
-			{if $is_admin}<td class="check">{input type="checkbox" name="selected[]" value=$row.id}</td>{/if}
+			{if $is_admin}<td class="check">{input type="checkbox" name="selected[%s]"|args:$row.line_id value=$row.id}</td>{/if}
 			{foreach from=$row key="key" item="value"}
+				<?php if ($key == 'line_id') continue; ?>
 				<?php
 				$column = $columns[$key] ?? null;
 				?>
 				{if $prev_id == $row.id && !in_array($key, ['debit', 'credit', 'account_code', 'line_label', 'line_reference', 'project_code'])}
 					<td></td>
@@ -73,11 +74,11 @@
 	{/foreach}
 	</tbody>
 
 	{if $debit !== null || $credit !== null}
 	<?php
-	$span1 = 0;
+	$span1 = -1; // Negative line_id (should count every column without label instead)
 	foreach ($row as $key => $v) {
 		if ($key == 'credit' || $key == 'debit') {
 			break;
 		}
 		$span1++;
@@ -96,10 +97,23 @@
 				</td>
 				{/if}
 			{/foreach}
 			<td colspan="{$span2}"></td>
 		</tr>
+		{if $is_admin}
+			<tr>
+				<td class="actions" colspan="{$span2 + $span1 + 2}">
+					<em>Pour les écritures cochées :</em>
+					<input type="hidden" name="from" value="{$self_url}" />
+					{csrf_field key="projects_action"}
+
+					{* As it needs a second formaction for this, and as submit is handled by automatic onchange event selecting ".actions select", the simplest (having only one action here), is to use a button instead of a <select> *}
+
+					{button type="submit" formaction="%sacc/transactions/actions.php"|args:$admin_url name="action" value="change_project" shape="plus" label="Ajouter/enlever d'un projet"}
+				</td>
+			</tr>
+		{/if}
 	</tfoot>
 	{/if}
 
 	</table>
 
@@ -111,33 +125,57 @@
 
 	<p class="help">{$count} résultats trouvés pour cette recherche.</p>
 
 	<?php
 	$id_column = array_search('id', $header, true);
+	$line_id_column = array_search('line_id', $header, true);
 	?>
 
 	<table class="list">
 		<thead>
 			<tr>
 				{foreach from=$header item="column"}
-				<td>{$column}</td>
+					{if 'line_id' === $column}
+						{if $is_admin}
+							<td class="check"><input type="checkbox" value="Tout cocher / décocher" id="f_all2" /><label for="f_all2"></label></td>
+						{/if}	
+					{else}
+						<td>{$column}</td>
+					{/if}
 				{/foreach}
 			</tr>
 		</thead>
 		<tbody>
 			{foreach from=$results item="row"}
 			<tr>
 				{foreach from=$row key="key" item="value"}
-					{if $id_column === $key}
+					{if $line_id_column === $key}
+						{if $is_admin}
+							<td class="check">{input type="checkbox" name="selected[%s]"|args:$row[$line_id_column] value=$row[$id_column]}</td>
+						{/if}
+					{elseif $id_column === $key}
 						<td class="num">{link href="!acc/transactions/details.php?id=%d"|args:$value label="#%d"|args:$value}</td>
 					{else}
 						<td>{$value}</td>
 					{/if}
 				{/foreach}
 			</tr>
 			{/foreach}
 		</tbody>
+		{if $is_admin}
+		<tfoot>
+			<tr>
+				<td class="check"><input type="checkbox" value="Tout cocher / décocher" id="f_all2" /><label for="f_all2"></label></td>
+				<td class="actions" colspan="100">
+					<em>Pour les écritures cochées :</em>
+					<input type="hidden" name="from" value="{$self_url}" />
+					{csrf_field key="projects_action"}
+					{button type="submit" formaction="%sacc/transactions/actions.php"|args:$admin_url name="action" value="change_project" shape="plus" label="Ajouter/enlever d'un projet"}
+				</td>
+			</tr>
+		</tfoot>
+		{/if}
 	</table>
 
 {elseif $count === 0}
 
 	<p class="alert block">Aucun résultat trouvé pour cette recherche.</p>

Index: src/www/admin/acc/transactions/actions.php
==================================================================
--- src/www/admin/acc/transactions/actions.php
+++ src/www/admin/acc/transactions/actions.php
@@ -8,18 +8,18 @@
 
 require_once __DIR__ . '/../_inc.php';
 
 $session->requireAccess($session::SECTION_ACCOUNTING, $session::ACCESS_ADMIN);
 
-$check = f('check');
+$selected = f('selected');
 
-if (!$check || !is_array($check)) {
+if (!$selected || !is_array($selected)) {
 	throw new UserException('Aucune écriture n\'a été sélectionnée.');
 }
 
-$transactions = array_unique(array_values($check));
-$lines = array_keys($check);
+$transactions = array_unique(array_values($selected));
+$lines = array_keys($selected);
 
 if (f('action') === 'payoff') {
 	Utils::redirect('!acc/transactions/new.php?payoff=' . implode(',', $transactions));
 }
 
@@ -51,13 +51,13 @@
 
 	Transactions::setProject($id, $transactions, $lines);
 }, $csrf_key, f('from') ?: ADMIN_URL);
 
 $from = f('from');
-$count = count($check);
-$extra = compact('check', 'from');
-$tpl->assign(compact('csrf_key', 'check', 'count', 'extra'));
+$count = count($selected);
+$extra = compact('selected', 'from');
+$tpl->assign(compact('csrf_key', 'selected', 'count', 'extra'));
 
 if (f('action') == 'delete')
 {
 	$tpl->display('acc/transactions/actions_delete.tpl');
 }