diff --git a/source/components/conversation/FormDecorator.js b/source/components/conversation/FormDecorator.js
index 0c0e236ad..22a70f8f0 100644
--- a/source/components/conversation/FormDecorator.js
+++ b/source/components/conversation/FormDecorator.js
@@ -134,7 +134,6 @@ export var FormDecorator = formType => RenderField =>
 
 		renderTitleAndAnswer(valueType, human) {
 			let {
-				name,
 				stepAction,
 				answer,
 				themeColours,
@@ -149,7 +148,7 @@ export var FormDecorator = formType => RenderField =>
 					</span>
 					<button
 						className="edit"
-						onClick={() => stepAction('unfold', name)}
+						onClick={() => stepAction('unfold', this.state.fieldName)}
 						style={{ color: themeColours.textColourOnWhite }}
 					>
 						<i className="fa fa-pencil-square-o" aria-hidden="true" />
diff --git a/source/components/conversation/Input.js b/source/components/conversation/Input.js
index 76bb8fbbd..2e9351f3e 100644
--- a/source/components/conversation/Input.js
+++ b/source/components/conversation/Input.js
@@ -78,14 +78,19 @@ export default class Input extends Component {
 			</span>
 		)
 	}
+	componentDidMount() {
+		let { stepProps: { inversions } } = this.props
+		if (inversions)
+			this.inverse(inversions[0].dottedName)
+	}
 	renderInversions() {
-		let { stepProps: { name: inputName, inversions } } = this.props
+		let { stepProps: { inversions } } = this.props
 		if (!inversions) return null
 
 		return (
 			<select
-				value={inputName}
-				onChange={e => this.inverse(e.target.value)}
+				value={inversions[0].dottedName}
+				onMouseDown={e => this.inverse(e.target.value)}
 			>
 				{inversions.map(({ name, title, dottedName }) => (
 					<option key={dottedName} value={dottedName}>
diff --git a/source/engine/generateQuestions.js b/source/engine/generateQuestions.js
index ce5394a24..c47f7935b 100644
--- a/source/engine/generateQuestions.js
+++ b/source/engine/generateQuestions.js
@@ -48,7 +48,6 @@ export let nextSteps = (situationGate, flatRules, analysis) => {
 	let missingVariables = collectMissingVariables(analysis.targets),
 		pairs = R.toPairs(missingVariables),
 		sortedPairs = R.sort(R.descend(impact), pairs)
-
 	return R.map(R.head, sortedPairs)
 }
 
diff --git a/source/engine/traverse.js b/source/engine/traverse.js
index e18d06427..b78137718 100644
--- a/source/engine/traverse.js
+++ b/source/engine/traverse.js
@@ -418,7 +418,8 @@ export let findInversion = (situationGate, rules, rule) => {
 	let fixedObjective = inversions
 		.map(i => disambiguateRuleReference(rules, rule, i))
 		.find(name => situationGate(name) != undefined)
-	if (fixedObjective == null) return null
+
+	if (fixedObjective == null) return {inversionChoiceNeeded: true}
 	//par exemple, fixedObjective = 'salaire net', et v('salaire net') == 2000
 	return {
 		fixedObjective,
@@ -430,6 +431,10 @@ export let findInversion = (situationGate, rules, rule) => {
 let doInversion = (situationGate, parsedRules, r) => {
 	let inversion = findInversion(situationGate, parsedRules, r)
 	if (!inversion) return null
+	if (inversion.inversionChoiceNeeded) return {
+		inversionMissingVariables: [r.dottedName],
+		nodeValue: null
+	}
 	let { fixedObjectiveValue, fixedObjectiveRule } = inversion
 	let fx = x =>
 		clearDict() && evaluateNode(
diff --git a/test/inversion.test.js b/test/inversion.test.js
index 804bea059..70b18c675 100644
--- a/test/inversion.test.js
+++ b/test/inversion.test.js
@@ -50,6 +50,36 @@ describe("inversions", () => {
     expect(analysis.targets[0].nodeValue).to.be.closeTo(2000 / (77 / 100), 0.0001 * 2000)
   })
 
+  it("should ask the input of one of the possible inversions", () => {
+    let rawRules = dedent`
+				- nom: net
+				  formule:
+				    multiplication:
+				      assiette: assiette
+				      variations:
+				        - si: cadre
+				          taux: 80%
+				        - si: ≠ cadre
+				          taux: 70%
+
+				- nom: brut
+				  format: euro
+				  inversions possibles:
+				    - net
+				- nom: cadre
+				- nom: assiette
+				  formule: 67 + brut
+
+			`,
+      rules = yaml.safeLoad(rawRules).map(enrichRule),
+      stateSelector = name => null,
+      analysis = analyse(rules, "brut")(stateSelector),
+      missing = collectMissingVariables(analysis.targets)
+
+    expect(analysis.targets[0].nodeValue).to.be.null
+    expect(missing).to.have.key("brut")
+  })
+
   it("should handle inversions with missing variables", () => {
     let rawRules = dedent`
 				- nom: net