diff --git a/docs/UseCase003-CreateNatureCheck/UC003-DCD.md b/docs/UseCase003-CreateNatureCheck/UC003-DCD.md
new file mode 100644
index 0000000..a347d7a
--- /dev/null
+++ b/docs/UseCase003-CreateNatureCheck/UC003-DCD.md
@@ -0,0 +1,116 @@
+```mermaid
+classDiagram
+    %% Services / ViewModels
+    class CreateNatureCheckService {
+      +IFarmRepository _farmRepository
+      +IPersonRepository _personRepository
+      +INatureCheckCaseRepository _natureCheckCaseRepository
+      +ICreateNatureCheckRepository _createNatureCheckRepository
+      +IEmailService _emailService
+      +Task<Guid> CreateNatureCheckAsync(CreateNatureCheck request, CancellationToken ct)
+      +Task<List<Farm>> GetFarmsAsync()
+      +Task<List<Person>> GetPersonsAsync()
+      +Task<List<NatureCheckCase>> GetNatureChecksAsync()
+    }
+
+    class ConsultantCreateNatureCheckViewModel {
+      +ICreateNatureCheck _createNatureCheckService
+      +ObservableCollection<Farm> Farms
+      +ObservableCollection<Person> Persons
+      +ObservableCollection<NatureCheckCase> NatureChecks
+      +RelayCommand RefreshCommand
+      +RelayCommand CreateNatureCheckCommand
+      +Task LoadAsync()
+      +Task CreateNatureCheckAsync()
+    }
+
+    %% DTO / Entities
+    class CreateNatureCheck {
+      +Guid NatureCheckId
+      +Guid FarmId
+      +Guid PersonId
+      +string FarmName
+      +int FarmCVR
+      +string FarmAddress
+      +string ConsultantFirstName
+      +string ConsultantLastName
+      +DateTimeOffset DateTime
+    }
+
+    class NatureCheckCase {
+      +Guid Id
+      +Guid FarmId
+      +Guid ConsultantId
+      +NatureCheckCaseStatus Status
+      +DateTimeOffset CreatedAt
+      +DateTimeOffset? AssignedAt
+      +string? Priority
+      +string? Notes
+      +Farm Farm
+      +Person Consultant
+    }
+
+    class Farm {
+      +Guid Id
+      +string Name
+      +string CVR
+      +Guid AddressId
+      +Address Address
+    }
+
+    class Person {
+      +Guid Id
+      +string FirstName
+      +string LastName
+      +string Email
+      +Guid RoleId
+      +Guid AddressId
+      +Address Address
+    }
+
+    class Address {
+      +Guid Id
+      +string Street
+      +string PostalCode
+      +string City
+      +string Country
+    }
+
+    %% Repositories / DB
+    class ICreateNatureCheckRepository {
+      <<interface>>
+      +Task<Guid> CreateNatureCheckAsync(CreateNatureCheck request, CancellationToken ct)
+    }
+
+    class INatureCheckCaseRepository {
+      <<interface>>
+      +Task<IReadOnlyList<NatureCheckCase>> GetAllAsync(...)
+      +Task<IReadOnlyList<NatureCheckCase>> GetAssignedCasesForConsultantAsync(Guid consultantId,...)
+      +Task<bool> FarmHasActiveCaseAsync(Guid farmId,...)
+    }
+
+    class uspCreateNatureCheck {
+      <<stored procedure>>
+      +@NatureCheckId OUTPUT, @FarmId, @PersonId, @FarmName, @FarmCVR, @FarmAddress, @ConsultantFirstName, @ConsultantLastName, @DateTime
+      note left: Inserts into dbo.NatureCheck (Id, Date, FarmId, PersonId, FarmName, FarmCVR, FarmAddress, ConsultantFirstName, ConsultantLastName)
+    }
+
+    %% Relations / dependencies
+    CreateNatureCheckService --> IFarmRepository : uses
+    CreateNatureCheckService --> IPersonRepository : uses
+    CreateNatureCheckService --> INatureCheckCaseRepository : uses
+    CreateNatureCheckService --> ICreateNatureCheckRepository : calls
+    CreateNatureCheckService --> IEmailService : sends email
+
+    ConsultantCreateNatureCheckViewModel --> CreateNatureCheckService : uses
+    ConsultantCreateNatureCheckViewModel --> Farm : displays
+    ConsultantCreateNatureCheckViewModel --> Person : displays
+    ConsultantCreateNatureCheckViewModel --> NatureCheckCase : displays
+
+    ICreateNatureCheckRepository ..> uspCreateNatureCheck : executes
+    uspCreateNatureCheck ..> NatureCheckCase : inserts row into dbo.NatureCheck
+
+    NatureCheckCase --> Farm : references
+    NatureCheckCase --> Person : references
+    Farm --> Address : has
+    Person --> Address : has
\ No newline at end of file